AMERICAN SOCIETY 


OP 


CIVIL ENGINEERS 


FLOOD PROBLEMS IN CHINA 


BY 

John R. Freeman, President, Am. Soc. C. E. 


Reprinted from Proceedings, Am. Soc. C. E., for May, 1922. 


























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Papers.] 


FLOOD PROBLEMS IN CHINA 

FLOOD PROBLEMS IN CHINA 
By John R. Freeman,* President, Am. Soc. C. E 


The inclusion of notes on the flood problems of China in this Symposium 
might at first view not seem helpful toward the solution of certain flood 
problems of America, for which engineers are striving; nevertheless, there 
\^re certain important facts about training rivers to cut their beds deeper 
where they flow over deep alluvial deposits, recently discovered in course of 
the speaker’s researches in China, that may prove of practical application 
in America and in other parts of the world. 

Floods in China imperil the lives of a greater number of people than 
anywhere else on earth. Many of the great famines of China are caused by 
floods which, spreading to shallow depths over vast areas, even thousands of 
square miles, drown the domestic animals, destroy the growing crops, and 
make impassable the few poor roads, so that relief cannot be brought in. 
Many other of the great famines are caused by an occasional shortage of 
rain in districts, where irrigation from controlled rivers or from storage 
reservoirs would insure food to lessen this starvation menace. In brief, there 
is no part of the world where the science and arts of hydraulic engineering 
could do more for humanity than in China. 

The regulation and guiding of certain of China’s great rivers in channels 
better adapted for flood control and for navigation present some of the most 
interesting problems of hydraulic engineering that can be found anywhere 
in the world, and the speaker has been led, through personal observation, to 
believe that the control of the rivers which cause these great floods is prac¬ 
ticable to a large extent by modern engineering, and that it can be carried 
forward whenever China’s domestic political affairs become straightened out 
and the inertia of extreme conservatism is overcome. 

Until twenty or thirty years ago, the world outside of China knew little 
about, these terrible floods, because means of communication within China 
were so poor that a knowledge of the facts filtered out slowly and imperfectly. 
For example, few now know that as recently as thirty-five years ago more 
than 1 000 000 people (some say 7 000 000) perished by drowning and starva¬ 
tion, resulting from one flood which came from a break through the south 
dike of the Yellow River, about 20 miles above Kai-feng City, and flowed 
southeasterly over a belt of nearly level country, perhaps 20 or 30 miles in 
width by 150 miles in length, into the Huai River. No accurate description 
of this outbreak or of its wide devastation appears to have reached Shanghai 
until after many weeks. Few to-day realize the awful devastation that fol¬ 
lowed the floods which, in August and September, 1917, surrounded Tientsin, 
the great commercial port of North China, submerged a large part of 15 000 
sq. miles of delta plain, containing 105 cities and 17 000 of the little Chinese 
farm-villages, numbered 5 600 000 sufferers (by partial count of the magis¬ 
trates), ruined crops estimated by the head of the Relief Commission to 


1113 


'T c - ! 


Consulting Hydraulic Engr., Providence, R. I. 




1114 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers. 


have been worth $22 000 000 * and caused a property loss several times this 
sum. Few who have not traveled in the Chinese deltas have any conception 
of the density of population or of the vast number of these little villages dotted 
everywhere over the fertile delta plain. 

Floods that in any other populous country would receive world-wide at¬ 
tention occur two or three times in almost every decade at one part or another 
of the great eastern Chinese delta plain. In July, 1919, while the surveyors 
on the Grand Canal were in the field, there was a flood from an outbreak 
through the Yellow River dike, that ruined the crops over about 125 sq. miles 



Fig. 3.—Chinese Picture Map of Kiang-su Flood. 

of fertile land, supporting 560 villages and 217 000 people, and caused dam¬ 
ages (as estimated by the local magistrates) to the extent of $350 000; and in 
July, 1920, a hundred miles away from the area just mentioned, following 
sudden rain, there was an outbreak through the dike of a little river, that 
spoiled crops said to have a value of $250 000, which outbreak was observed 
by the principal American field engineer. These two floods, of 1919 and 
1920, were so commonplace in comparison with the great floods which always 
threaten, that so far as the speaker could learn, they escaped all notice in 
the several important English language newspapers published in China. The 
summer of 1921 brought a repetition, for perhaps the hundredth time in his- 

* The distinction between U. S\ gold and “Mex.” silver dollars, an ordinary basis for 
estimating values in China, which are worth about one-half the gold dollar, has to be made 
PP ubllca tions dealing with China. All values in this paper are calculated in U. S. 
gold dollars, at two silver for one gold. 





















Papers.] 


FLOOD PROBLEMS IN CHINA 


1115 


tory, of great floods in Kiang-su Province and of another break in the Yellow 
River dike somewhere on the lower river, which is said to have caused great 
damage and a shifting of several miles in length of its channel, although no 
description of it has yet reached America. 

In Kiang-su Province, along the branching outlets of the Huai River, 
north of the Yang-tze River and east of the Grand Canal, there is a flat 
delta plain of extremely fertile land extending nearly 100 miles north and 
south by about 50 miles east and west, which vast area, time after time, has 
been covered with water from the Huai floods, deep enough to drown most of 
the domestic animals, ruin the crops, and consign multitudes of people to 
starvation. An old Chinese picture map of this region in flood is shown in 
Fig. 3.* The area shown flooded covers about 4 500 sq. miles. This district 
which now supports an impoverished population said to number about 
2 000 000, could be made, by means of construction works which the speaker 
believes practicable, to support, in comfort and safety, a population far greater 
than at present.]- 

The great industrial leader, Chang Chien, says, in his report of 1919, 
urging National action, “Within this district along the Huai River below the 
City of Wu-hu, in the past thirteen years, there have been six serious famines 
affecting thousands and thousands of people.” 

In the speaker’s two brief tours of China, he has seen enough of some of 
these regions menaced by flood to convince him that no country has greater 
need of careful engineering research and sound cautious advice; and from his 
studies for the improvement of the Grand Canal and of the Yellow River, 
he is confident that great relief can be secured by an expenditure which rel¬ 
atively is not large and which can be forthwith recovered in the increased 
value of the land reclaimed. The construction can be performed mostly 
with hand implements, by native labor, which badly needs employment, at a 
smaller cost than by steam shovels, industrial railways, or dredges. 

No part of the world gives greater opportunity for beneficent service to 
suffering millions of worthy, kindly, industrious people, by means of engineer¬ 
ing skill, combined with a substantial construction-loan to the Chinese 
Government. 

Concentration of the Floods 

The outline map of China, Fig. 4, shows that run-offs from the principal 
river drainage basins are gathered into remarkably few main outlets to the 
sea, there being, within 2 500 miles of main coast line, measured without 
including the sinuosities, only five or six outlets to carry off the discharge from 
a catchment area about equal to the United States east of the Rocky Moun¬ 
tains. Naturally, the flood characteristics of these widely separated dis¬ 
tricts differ greatly. 

* From Fr. Gandar’s “Histoire du Canal Imperial.” 

t Ex-Minister Reinsch says in ‘‘An American Diplomat in China” (p. 60) : ‘‘The people 
of the Huai Region, secure and affluent, might be easily increased by twenty million living 
heirs of a fifty-century old civilization. 




1116 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers. 


Almost nothing was known of the detailed topography of the interior of 
China, until within the past 20 years, except from the journals written along 
single lines of travel by Abbe Hue, Pumpelly, and Kichthofen; and precise 
information about the floods of these five great river systems is still limited 
to a few areas, large in themselves, but small compared with the whole of 
China. 



These particular flood areas about which something is known are mostly 
near the commercial centers. Doubtless these districts are the worst afflicted, 
because they are within the vast delta plains where a flood can spread. 
Back from these deltas near the sea, Chinese topography presents vast areas 
of hill and valley, which doubtless possess all ordinary varieties of the flood 
problems found in other parts of the world, that come from torrential rain¬ 
fall and run-off in relatively narrow valleys, with great and rapid range from 
normal to flood height; for China has many rainfall records of 8, 12, and 
even 15 in. depth falling in a single storm, which equal and exceed that in the 
great storm of the Miami Valley. 










Papers.] 


FLOOD PROBLEMS IN CHINA 


1117 


This paper does not deal with those floods of upland regions. They concern 
fewer people and probably their control is to be found mainly in the slow 
processes of systematic forestry, or perhaps by barrages, such as are used in 
certain Swiss valleys, for preventing the landslides caused by torrents, from 
undercutting the steep hillsides. 


Re-Forestation and River Training 

The situation in general for flood relief requires much more than sys¬ 
tematic forestry, although the sooner widespread re-foresting of the hills is 
vigorously undertaken, the better. The thickly settled lowlands of China are 
almost treeless, except small spots around the graves of ancestors, and dur¬ 
ing the past few centuries the uplands far back along the rivers have been 
robbed of their natural protection; it is certain that the cutting of the 
forests has had much to do with the present disastrous conditions. For ex¬ 
ample, up stream from Tientsin, vast areas of hills, from which floods descend, 
are said to have been stripped of their natural forest cover centuries ago and, 
consequently, their humus and their porous top soil have been largely washed 
away and the subsoil cut into gullies by torrential rains. Many of these 
steep slopes which, although unfit for growing grain, might be made to grow 
much needed timber, are now so bare that they shed water almost like a tiled 
roof. 

Although forest litter, humus, and forest shade will unquestionably delay 
run-off from rain and snow in China as elsewhere, the disastrous delta floods 
on the Yellow and the Huai Rivers come largely from climatic and topographic 
conditions far beyond forest control. Forestry would protect the hill slopes and 
aid in moderating the lowland floods, but in the vast Chinese deltas, quicker 
positive safeguards are needed by means of channel control, new channels, 
and strong dikes, and these methods of relatively prompt relief seem feasible 
to the speaker whenever funds and proper direction can be had. 

It seems probable that the new works of river training and dike building 
needed for the complete protection of certain large areas, which works, although 
extensive, are of a simple character, will cost annually far less than the 
present unreliable structures, and it also appears probable that the value of 
waste land that can be reclaimed by these new works could promptly be made 
to pay back to the Government, their entire cost and, in addition, bring 
prosperity to a vast impoverished region, and to other regions bring safety 
from impending disaster. All this complete flood protection, however, is 
no short and simple task, nor can the works be properly designed until 
scientific tests and painstaking observations have been made. 

T]ie speaker will present, in this paper, various tentative plans for flood 
relief in certain localities. Although these plans are the result of much study, 
and observation, he desires it clearly understood that, in their present form, 
they are suggestive rather than conclusive, and are subject to revision after 
more complete surveys. They are presented now in the hope of stimulating 
further investigation in the immediate future. 


1118 


[Papers. 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 

Some Localities Having Important Flood Problems 

From north to south there are five principal localities within these mam 
Chinese drainage basins, shown on the map, Fig. 4, in which flood relief 
needs to be intensively studied and great works constructed whenever the 
Government becomes stabilized and capital gains confidence so that means 
can be provided. These localities are, as follows: 

(1) .—In the flat, level plains of the drainage basin that has its outlet past 
the great commercial city of Tientsin. This region suffered terribly in 
August and September, 1917. An area of about 12 000 sq. miles was sub¬ 
merged, and more than 1 000 000 people, mostly farmers, are said to have 
been driven from their homes. A property loss of more than $25 000 000 is 
said to have been incurred in this one flood with consequential damage of 
perhaps $50 000 000. 

(2) .—In the delta of the Yellow River, or Hoang Ho, along the river’s 
400-mile course through the delta. During the historic period of 4 200 years, 
this region has been ravaged time and again by floods in one place and an¬ 
other. These overflows come from breaks in the great dikes and occasionally 
cause a wide change in the river’s source. So terrible have been these visita¬ 
tions that this river is often called “China’s Sorrow”. The conditions are 
aggravated by the silt burden, brought from the vast and easily eroded loess 
deposits of the Provinces just up stream from the delta, which make the 
Yellow River probably the muddiest great river in the world. 

(3) .—The Huai River District in Kiang-su Province below Wu-hu. About 
5 000 sq. miles of this peculiarly low and level delta region is said to be 
frequently inundated, with famine often following flood. The land is ex¬ 
ceptionally fertile and normally gives two crops per year, so that, for thou¬ 
sands of years, intensive cultivation has been continued in spite of disasters 
which, sometimes, have brought death to thousands and, at other times, have 
merely destroyed the second of the two yearly crops. 

(4) .—Along the Yang-tze River below Ichang. Here, in the Grand Gorges, 
the river floods are said to rise 80 ft., and below Hankow the flood discharge is 
said to reach about 3 000 000 sec-ft., which is about 50% larger than the greatest 
flood discharge of the Mississippi River at New Orleans, La. The Yang-tze 
River, although turbid, brings down less silt than the Yellow River. Its delta, 
therefore, grows more slowly. Its whole regimen has become well established, 
and the flood problems are mainly those of ordinary dikes combined with river 
training on a mighty and forbidding scale, because of the depth and volume 
of water. The charts show dozens of spots where the swirl of the flood cuts 
pools more than 100 ft. deep, and it is no light problem to work out shore 
protection that will hold so deep a bank of soft fine-grained river silt when 
attacked by the undercutting of such a flood.* 

(5) .—In Southwestern China the valleys of the North, East, and^West 
Rivers, in the country around and back from Canton. Near the important 
City of Wu-chow, the great West River is said to rise 50 and even 80 ft. in 
extreme floods, and at the rate of 1 ft. per hour. 

* The Mississippi River, at Greenville, Miss., rises about 50 ft. in extreme floods, and 
has a flood depth in main channel upward of 100 ft. 



Papers.] 


FLOOD PROBLEMS IN CHINA 


1119 


(6) .—The improvement of navigation also presents incidental problems 
of flood scour, in addition to those of protection from inundation. There 
are particularly great and difficult problems of river training for improving 
navigation, and problems of utilization of flood flow for scour of channels 
for harbor improvements, to be found* on the Yang-tze near Shanghai, on the 
Min River near Foo-chow, and all along each of these five or six great silt¬ 
bearing rivers of China proper. 

The great depth of the silt deposit in these Chinese deltas gives unlimited 
scope for the river to scour its bed deeper when confined in a generally straight 
and narrow way. 

(7) .—Outside the limits of China proper, to the northeast in Manchuria, 
there are great flood problems along the Liao River which rises in the Mon¬ 
golian slopes and brings down silt that forms a harbor bar at New Chwang. 
On the other side, 17 000 miles away, in a straight line to the southeast, in 
French Indo-China, the lower course of the Red River presents serious flood 
problems which the French Government is said to be considering. 

Besides the large problems cited, there are many smaller ones in drainage 
basins from 20 by 100 miles to 40 by 100 miles in extent, that are almost too 
small to show on the map of all China, to which floods may come once in 10, 
20, or 40 years, that are terrible enough to the many people living on little 
farms or in little villages in their path. Examples of them were found in* 
course of the Grand Canal surveys along the Wen River and in the Red 
Cross reconnaissance on the Yi River. Doubtless there are a hundred of 
these minor areas in fertile and densely populated parts of China, each of 
which has its own important flood problem which can be solved so as to 
bring a greater measure of security and happiness, whenever the Government 
becomes stabilized, a broader community spirit developed, and when the multi¬ 
tude of young Chinese, now studying modern engineering methods at home 
and abroad, are given the means wherewith to work. 

Ancient Chinese Flood Protection 

The Chinese have had to contend with the problems of flood control by 
dikes during their whole historic period of about 4 000 years and have de¬ 
veloped some wonderfully good technique in many matters of dike building 
and in the repair of dike breaks. Although in the science of river training, 
they (and all engineers) still have much to learn, they have, in many great 
works, shown skill as hydraulic engineers. They have had'some of the most 
difficult problems in the world with which to contend. 

One of their most venerated men, of the half-legendary days of 3 000 
years ago, was Yu, their great hydraulic engineer, to whose memory many 
temples were built and who, after a period of trouble, was entrusted with 
the conservancy of rivers throughout the country. He regulated the waters 
so wisely, it is said, that with his precepts faithfully followed there was no 
serious trouble for more than 1 000 years until “the period of the warring 
States”. Tradition says, “Yu labored thirteen years, sparing neither trouble 
nor fatigue, nor even once entering his own home, though he passed three 
times before its door.” That “he had boats for travel by water, chariots for 


1120 PROCEEDINGS, AM. SOC. C. E., MAY, 1922 [Papers. 

travel by land, sledges for mud, with relays of men to draw them.” “He dug 
nine great channels to conduct the waters to the sea, and he is supposed 
to have organized the building of great systems of dikes. In the great fertile 
Province of Szechwan, many travelers have (^escribed great irrigation works and 
flood channels planned more than 2 000 years ago by an engineer, whose rules 
are said to be still implicitly followed. Tributary to the Grand Canal, at Tai- 
tsun-pa, there is a feeder dam, which the speaker has examined, of masonry 
resting on small piles driven into a soft sand foundation, that was admirably 
built about 500 years ago. The sea wall, of coursed cut stone, 25 ft. high, that 
protects the coast for many miles easterly from Hangchow, is a structure built 
about 400 years or more ago, of which any modern engineer might be proud. 
The fact that, during 538 years, the great restless Yellow River was held to 
its course on a silted bed several feet above the level of the ground on either 
side, within dikes built of soft friable river silt, carefully consolidated by 
tamping and protected from the erosion of impinging currents in many places 
only by groynes and revetments of earth bound together with perishable millet 
stalks, speaks volumes for the skill and resources of these Chinese “Old 
Masters of River Control”. 

Preliminary Surveys in Progress 

In all the localities previously mentioned, investigation is now being 
carried on under the Chinese Government; but everywhere* this work seems to 
be mostly in the surveying rather than in the engineering stage. It is far 
easier to make a tolerable survey than to make a good design and then 
establish confidence in it; and one gets an impression that the authorities 
having certain of these matters in charge are staggered by the size, com¬ 
plexity, and uncertainty of their problems, or are floundering in a “Slough of 
Despond”, and that some of them may be forced, by pressure of the public 
demand for “making the dirt fly”, into constructions that will not stand the 
test of time, and of which they themselves may have doubts. The data collected 
in these surveys and investigations are few in comparison with the vast ter¬ 
ritories in China affected by flood. 

For investigations within the Hai River Drainage Basin, following the 
great Tientsin flood of September, 1917, the Chinese Government organized 
the Chihli River Improvement Commission which, under the guidance of 
English, American, and Chinese engineers, including three members of this 
Society, has, for about four years, been making topographic and hydrographic 
surveys, from which data, works may be planned later. 

All along the Grand Canal in Shantung Province, the China Grand Canal 
Improvement Board, under the supervision of American engineers, members 
of the Society, has made extensive topographic and hydrographic surveys, and 
a reconnaissance survey of the Yellow River’s course and its dikes for 200 
miles up stream from the Grand Canal crossing. Plans have been devised for 
the immediate reconstruction of 253 miles of the Grand Canal, whenever 
this work can be financed; but from lack of funds, owing to the difficulty of 
selling Chinese bonds under present disturbed political conditions, the en¬ 
terprise is now marking time. 

* Except on the Min Estuary. 



Papers.] 


FLOOD PROBLEMS IN CHINA 


1121 


Along two or three portions of the 400 miles of the Lower Yellow River 
within the delta plain, the Provincial Conservancy Boards are making out¬ 
line surveys of the river's course and of its dikes, but with little attention 
to accurate hydrography or levels so far as the speaker has been able to learn. 
Meanwhile, the Chihli River Commission is gauging the Yellow River flow 
and measuring, at frequent intervals, the percentage of silt that it carries, at 
the Tientsin-Pukow Railroad Bridge. The daily height of the Yellow River is 
recorded also at the Peking-IIankow Bridge, 302 miles up stream. 

In Kiang-su Province, under the leadership of one of the most remarkable 
men in China, His Excellency, Chang Chien—classical scholar, Confucian 
philosopher, captain of industry, and philanthropist, full of the spirit of 
service to his fellow men—who seeks means for protecting his Province from 
floods, much of the delta land is being covered by a topographic survey made 
wholly by Chinese surveyors, that has been in progress for ten years, with 
Ym. contours over large critical areas. This is accompanied by occasional, 
more or less accurate, river-flow gaugings. 

For several years, the Harbor Board of Shanghai, controlled chiefly by 
the English, American, and French commercial interests, with a view chiefly 
to the improvement of navigation, has been making an excellent systematic 
and thorough survey of the neighboring Yang-tze River and its small tribu¬ 
tary river, the Whang-poo, on which Shanghai is situated, under Capt. A. Y. H. 
von Heidenstam, M. Am. Soc. C. E., assisted by E. C. Stocker, Assoc. M. Am. 
Soc. C. E. 

At Eoo-Chow, some good river-training work is said to be in progress, 
mainly for improving the entrance from the sea to the harbor, in charge of 
Mr. J. R. Hess, Nf. Art. Soc. C. E.. 

In Southwestern China, along the great West River and other rivers near 
Canton, some excellent preliminary hydrographic studies relative both to navi¬ 
gation and flood problems have been in progress for five years, in charge of 
Capt. Olivecroner, a Swedish engineer. 

As a whole, the outlook for important construction, everywhere, is poor, 
because of internal political conditions, the impossibility of the present Gov¬ 
ernment securing adequate funds, either by internal taxes or outside loans, 
and by the lack of community spirit, but the speaker believes that sooner or 
later China will find a way to work out its own salvation, and that the present 
outlook on stagnation will suddenly change. 

Although China proper presents a range of latitude and longitude about 
equal to that of the United States east of the Rocky Mountains, this paper 
will be confined to the first three problems previously mentioned, which are 
found in the northeastern delta plain of China, north of the Yang-tze River, 
within an area, which, on a map of the United States, would about cover a 
triangle with corners at Buffalo, U. Y., Boston, Mass., and Washington, D. C. 
First the flood problems of the Yellow River, “China's Sorrow”, will be briefly 
discussed. 

Flood Problems of the Yellow River Delta 

By far the largest of the Chinese deltas is that of the Yellow River which, 
with a radius of about 400 miles and an apex angle of about 90°, from its 


1122 PROCEEDINGS, AM.‘SOC. C. E., MAY, 1922 [Papers. 

mountain exit, slopes seaward with wonderful uniformity at the rate of 10 in. 
per mile measured on a straight line, or about 8 in. per mile as measured 
along the river’s winding course. Through millions of years this delta cone 
has been built up by deposits of fine-grained silt, brought down by the floods 



Fig. 5. 

from the vast loess deposits of Shansi and other Provinces. The flatness of 
the surface of this vast delta-cone is the cause of the great width and wide 
range to which a flood may spread when it escapes from the river’s dikes. 
This flat slope may be due to the extreme fineness of the particles of silt, 










Papers.] 


FLOOD PROBLEMS IN CHINA 


1123 


which are mostly derived from the erosion of vast beds of loess, supposed to 
be accumulations of wind-blown dust, that originally came largely from the 
vast Gobi Desert. A moderate current can carry this fine-grained material a 
long way. 

The Yellow River is not large in volume, compared with other great 
rivers of the world, although it is about 2 350 miles long, without counting 
the minor bends, and drains about 305 000 sq. miles. Within the historic 
period of about 4 200 years, the Yellow River has meandered and shifted 
from north to south, and back again, through this delta plain, occupying the 
nine widely divergent channels shown in Fig. 5. 

The courses followed in these migrations appear to have first been brought 
to the attention of the outside world by the American explorer and geologist, 
Raphael Pumpelly, about 1865, in a series of small maps. The speaker had 
the map, which is presented on a reduced scale in Fig. 5, prepared in China, 
in 1919, by tracing on a sheet about 4 ft. square, the several courses laid down 
on a series of Chinese maps brought to his attention by the engineers of the 
Chihli River Improvement Commission. These maps were the work of a 
Chinese historian of about 100 years ago, who based them on the investiga¬ 
tion of a Chinese author of about 200 years ago.* The Chinese have had 
some remarkably painstaking scholars and historians. 

When a complete topographic map of China on a large scale is prepared, 
many additional details will probably be secured, because when one travels 
across the delta, many depressions, sand dunes, abandoned dikes, and other 
indications of ancient channels are found. Many town and provincial records 
have been kept for centuries, which note changes and floods with evident care. 
It is important that all these sources of data be searched and that a complete 
contour map be made of all the delta, showing all ridges and drainage channels, 
as a basis for many possible improvements; but the solving of the main problem 
of flood protection need not wait for this. 

Since time immemorial, the river floods have been confined between dikes 
built of river silt, well-tamped into place, which dikes are guarded from 
erosion, wherever the river threatens, by spur-dikes or groynes commonly 
built with a facing of loose stone rip-rap over a core of earth and millet 
stalks, but sometimes built only of bundles of millet stalks, tied together 
with straw ropes, packed with earth, and pinned down with small stakes. 
This turning away of an impinging flood by spur-dikes is made easier by the 
great width of open ground between the dikes, which area is largely made 
unavailable for agriculture by the danger of flooding. On some of the 
higher silt banks of the flood-plain between the dikes, the farmer often sows 
his seed and takes a chance of loss of harvest if the annual flood arrives early. 

Excessive Width Between Dikes 

In general, along the upper 200 miles within the delta, and as shown in 
Fig. 6, these inner dikes are from 4 to 8 miles apart, although the necessary 
channel width at ordinary stages is only about i mile, and for floods, less 
than i mile. The water sometimes spreads in a thin sheet over the elevated 

* “Notes on the Tribute of Yu’’, by Hu Wei, published in 1708. 




1124 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers. 


terrace of silt deposited between the normal shore line and the dike, to a much 
greater width than £ mile, sometimes to the entire width between the inner 
dikes; but there are localities, as at Wei-chia-shan and Chang-kou, where the 
river happens to be confined between rocky hills projecting through the deep 
silt deposits, and here it flows in apparent comfort in a channel having a 
flood width of only about £ mile, without abnormal fall, over a bed easily 
erodible to any necessary depth. Careful study of soundings and velocity 
measurements made of these localities proves that mile is ample width of 
channel for carrying the greatest flood, and indicates that one-third of the 
length of the magnificent, German-built bridge at the Tientsin-Pukow Kail- 
road, at Lo-kou, would have sufficed, with great saving of cost if accompanied 
by some adequate simple river-training works. 



This great excess of width between dikes beyond that necessary for the 
flood channel or, for example, 5 miles instead of £ mile, gives space for an 
ever-changing meander between these widely separated dikes, and when the 
bank is threatened by erosion this space permits the river to be deflected away 
from the dike on a long new course by means of new spur-dikes. This method 
of obtaining safety, while convenient, is extremely wasteful of land. The 
speaker believes that a great saving of land is possible and that, by methods 
to be described later, the safety against the outbreak of a flood can be greatly 
increased. 

In 1919, the Grand Canal Improvement Board, in the course of investiga¬ 
tions supervised by the speaker, surveyed and ran levels for several hundred 
miles along the Yellow River dikes and leveled on cross-sections across the 
channel between the dikes, and extended these levels several miles across the 
plain outside the dikes, so that positive information at many places is now 


























Papers.] 


FLOOD PROBLEMS IN CHINA 


1125 


available as to the relative elevations of river surface and of the ground out¬ 
side, and, also, the slope of the river in flood and in drought, is known. 

In December, 1919, the speaker cruised in a small boat, many miles down 
the river from near the apex of the delta, studying the dikes, currents, 
channel, sand-bar formations, and sites of some of the most famous dike 



breaks, particularly those of 1869, 1887, aiid 1851. There seems to be hardly 
a 5-mile stretch of dike that has not been breached within the last few centuries, 
if the loops and groynes may be taken as evidence. 

This excessive width between dikes prevails mostly within the up-stream 
215 miles of the river’s course within the delta. In the new course down near 
the old and new Grand Canal crossing, the inner dikes are little more than 
1 mile apart for a distance of 20 miles along the river, but, here, the bed 

















1126 PROCEEDINGS, AM. SOC. C.E., MAY, 1922 [Papers. 

is not elevated above the plain outside the dikes. Seventy miles farther down 
stream, below the Tientsin-Pukow Railroad Bridge, the inner dikes average 
only about 1£ miles apart for the first 20 miles below the bridge and about 
2 miles apart for the next 50 miles, according to the map in Capt. Tyler’s 
report of 1905. 

An example of the relations of channel, main dike, loop-dike, and spur- 
dike, is shown in Fig. 7, which was traced from a Chinese conservancy map 
of the part of the river near the boundary between Chihli and Shantung 
Provinces, and begins about 60 miles down stream from the end of the sec¬ 
tion shown in Fig. 8. It is reproduced because it is typical of many miles 
of dikes. The sites of threatened or actual breaks, more or less ancient, are 
shown by loops of adjacent dikes built either as a part of the scheme of regain¬ 
ing control or as a precaution at a threatened break. Records of attempts 
of the river to undermine and cut through the dike are shown by the succes¬ 
sion of stone groynes or spur-dikes, which were constructed, more or less 
hastily, to deflect the river from the threatened dike. 



The general form and dimensions of these Yellow River dikes are shown 
in the photographs, Figs. 9 and 10. Fig. 9 shows the outer side of the main 
south dike at the site of the break of 1887, described subsequently. Fig. 10 
is a view of a series of spur-dikes, looking up stream. Fig. 11 is a view of 
a dike gullied by rain, showing the friable nature of the earth. 

Plate XX and Fig. 12 show several cross-sections surveyed in 1919 approxi¬ 
mately at right angles to the river’s course, in order to find the relative eleva¬ 
tion of the river and that of the broad plain outside the dikes, and serve to 
explain the tendency of the Yellow River to break out, cause terrible floods, 
and change its course across the river bed. These sections give the first 
















Papers.] 


FLOOD PROBLEMS IN CHINA 


1127 



Fig. 9.—Outer Side of Main South Dike at Site of Break of 1887. 



Fig. 10.—Series of Spur-Dikes, Looking Up Stream. 



M 


FiCx, 11.—View of Dike Gullied by Rain 


















t 


Papers.] 


FLOOD PROBLEMS IN CHINA 


1129 


published accurate instrumental levels of wide range across the dikes and the 
outside plain of the Yellow River. The gross exaggeration of this scale, 
1 000 vertical to 1 horizontal, should be kept in mind while examining these 
cross-sections. This magnification of vertical scale was required to make 
plain the differences of elevation in a country so extremely flat that to the 



eye it appears a vast level plain. Plate XX shows a greater width of the plain 
than Fig. 12 which is on a larger scale and shows sections above and below 
the break and change of course in 1851. 

Some of those cross-sections of special interest are that at San Yi Chai, 
Fig. 12, taken 5 miles above the great break, which shows plainly the super- 







































































































































































































































































































































































































































1130 PROCEEDINGS, AM. SOC. C. E., MAY, 1922 [Papers. 

elevation of the river bed above the plain, and those at, respectively, 8 miles, 
28 miles, and 88 miles, down stream from the break, which show no elevation 
of the river bed above the plain. 

There has been much controversy among American engineers, interested 
in the Mississippi levees, about the super-elevation of the bed of the Yellow 
River above the outside plain, and some good men of high authority have 
denied its existence. The proof is now available. The facts are that for 50 
miles or more in length, above the outbreak of 1851 and along the old course 
below this outbreak, the river bed is slightly above the plain, whereas, along 
the new course, it is slightly below the plain. 

The three sections at the top of Fig. 12 are along the new course and 
those lower on the diagram are along the old course. All are drawn looking 
down stream and are arranged in regular order with the sections farthest 
down stream, or farthest east, at the top of the diagram. 

These cross-sections surveyed in 1919 indicate that for about 80 miles of 
its length through the delta, or from the Peking-Hankow Railroad down to 
near the great break of 1851, the flood surface of the river is about 20 or 
25 ft. higher than the level of the ground outside the inner dikes, and that 
the low-water surface is about 5 to 10 ft. higher than the ground outside 
the dikes; they also show that the normal bed of the river at low stages, 
averages about 5 ft. higher than the general level of the country, this bed 
probably having been raised a few feet by deposits of silt, to provide the 
needed slope for overcoming the friction of the increased length, as the river 
built its mouth farther out into the sea with the silt deposits of centuries. 

Sections taken by the Kiang-huai Chinese surveyors along the abandoned 
channel of the Yellow River easterly from the Grand Canal in Kiang-su 
Province, in which the Yellow River flowed for 528 years until 1851, show 
that the super-elevation of the river here averaged about the same as that 
just described above the break of 1851, and thus curiously differs from the 
condition without super-elevation below the break of 1851, where the river 
has now been flowing for 70 years. 

A longitudinal profile along the river surface and along the tops of both 
dikes also has been made up from this reconnaissance survey. This profile 
shows a remarkably uniform general slope of the river surface, except that 
there is a drop of about 10 ft. more than normal, within a few miles of the 
break of 1851, resulting in a largely increased slope for this distance. This 
is worthy of careful examination in the field, and why it has not cut back 
further and lessened this slope remains to be explained. Both the north and 
south river dikes are higher and thicker along the old course above the break 
of 1851, than along the new course below it. 

In general, the accurate levels of 1919 confirm the statements of the 
English engineer, G. S. Morrison, and those of the Dutch engineers, Yon 
Schermbeck and Yisser, who visited the break of 1887 in 1888 and 1889, 
respectively, and reported the river bottom about 5 ft. above the level of the 
plain, and they disprove the statements of Gen. Wilson based on observations 
with only a hand-level, that no super-elevation of bed existed at the site of 


PLATE XX. 

PAPERS, AM. SOC. C. E. 
MAY, 1922. 
FREEMAN ON 

FLOOD PROBLEMS IN CHINA. 




20 16 1 
CROSS SECTION NO. 7 


\WYj 


a r wn 

YY/SA 


I 'msssmm 


YELLOW RIVER CROSS SECTIONS 

LOOKING DOWNSTREAM 

All Elevations are in Meters above Taing-Tau 
Datura which is 2.3 meters below Sea Level 
Note: 

In all sections, the position of South 
Inner Dike Is Placed in same Vertical 
at Station O. 


Distance in Kilometers Northerly from South Inner Dike 


CROSS SECTION NO. 2 


35 30 25 20 

Distance in Kilometers Northerly from South Inner Dike 


Approximate Distance 
along Curving Channel 
Upstream from Tientsin 
Pukow Bridge at Lokou 


60 

Cross Section No.7 
is 64.0 £ miles’(87.0km.) 
Below Break of 1852 













£ 

L° 


% 



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Distance in Kilometers 
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Oi l River BedO\ 


£ Survey Side Line to Kal Peng 
'City near Cross Section No. 5 


6 0 
CROSS SECTION 


16 


35 30 26 

Distance in Kilometers 
Northerly from South Inner Dike 


a 

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a 

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10 16 

CROSS SECTION NO. 4 


288 Miles 
463 km. 


170 Miles 
273 km. 


214 Miles 
343 km. 


267 Miles 
429 km. 


























































































































































































































































































































































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Papers.] 


FLOOD PROBLEMS IN CHINA 1131 

the break of 1851. None of these previous observers seems to have had the 
means for widely extended accurate leveling. Also, the speaker’s recon¬ 
naissance disproved the old idea that there is a double set of good dikes, 
outer and inner, most of the way along the Yellow River, as a safeguard 
against the coursing of a flood far across the country, as in 1887. 

Absence of Outer Dikes 

Within these regions of super-elevation of river above the outside plain, 
which extend along the present course of the river for perhaps 80 miles 
down stream from the Peking-Hankow Railroad Bridge, greater danger is 
involved in the rupture of a dike, particularly on the south side where no 
outer line of dike exists; and it will be noted from Pig. 5, that most of the 
migrations have started on their new course from outbreaks in this region 
of super-elevation of bed. There is an outer line of dikes farther down stream, 
on the south side. 

Along the north side of the river, near the apex of the delta, the so-called 
north outer dike of the present channel seems to be a south dike of a more 
ancient channel and below the break of 1851 the so-called south outer dike 
possibly may be one of the dikes of the river’s course of 1194 to 1289; and 
this ancient abandoned river channel may have provided the site for an 
ancient canal described by the old records as existing in that vicinity. These 
outer dikes do not parallel closely the inner dikes, but are irregular and, in 
some localities, ten miles away from the inner dike. In general, the loca¬ 
tion or existence of this outer dike would seem at present to be more a matter 
of the accidental position of an ancient river course than of design for present- 
day protection. Nevertheless, these outer dikes sometimes serve a useful 
purpose in checking the course of a flood that has broken through the inner 
dike and an example of such a checking and turning back of a minor flood 
will be given subsequently. 

Yellow River Flood Discharge 

The flood discharge of the Yellow River is from 200 000 to 300 000 sec-ft. 
and perhaps more, a few times in each century. In 1919, a flood higher than 
any of the preceding ten years, had a peak discharge of about 280 000 sec-ft., 
which is about the same as the maximum flood volume of the Mississippi 
above the confluence of the Missouri. The ordinary low-water flow is about 
10 000 sec-ft. and continues ordinarily from October to May. Although the 
discharge from low water to high water thus increases twenty-five-fold, the 
mean velocity is increased only about two and one-half times. The necessary 
increased area of cross-section is obtained partly by the rising and spreading 
of the waters, but largely also by the river digging its bed deeper and wider, 
as will be described later. 

This flood volume of the Yellow River is only about one-tenth of the flood 
volume of the neighboring Yang-tze River, but, nevertheless, it is a mighty 
flood and continues high from one to two months. The main flood of the 
year comes at any time from July to September, and is caused mostly by 


1132 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers. 


rains or melting snows in the mountains and valleys, hundreds or thousands 
of miles up stream from the apex of the delta. Sometimes, brief important 
floods may come from heavy rains in the near-by mountains. 



Figures Show 
depths m meters 
of fresh sediment avs 
measured in mud-cracks 

Groups of buildings 
Shown thus m 

Investigation 

of 

Yellow River Flood Break 

OP JULY 24* > 1919 

nr)VLDv9f s *0O mC ^ 

Statute Miles 


Fig. 13. 


The log of a typical high flood, the highest of ten years, is given in Fig. 
18. A good idea may be had of the variation from year to year in range, 
height, and duration, from the daily stage records, kept since about 1908 







Papers.] 


FLOOD PROBLEMS IN CHINA 


1133 


at the two railroad bridges, which show that the main flood may come at 
any time from July to September, but most commonly occurs in August, and 
continues for about five to eight weeks. 

An isohyetal map of China (Fig. 25), is presented subsequently in this 
paper, in connection with Kiang-su problems; but rainfall studies give little 
aid on the flood problems of the Yellow River. 

It is a remarkable fact that the Yellow River receives no tributaries within 
its long course of 400 miles through the delta, with the exception of the 
Ta-ching Ho, the bed of which it usurped in 1851. Obviously, they could not 
get in through the dikes. Moreover, here, as in most deltas, and as shown 
in Plate XX, the river flows along a sort of crest, with the ground at right 
angles on both sides falling away on a slope, imperceptible to the eye, of 
only 6 in. to 1 ft. per mile. This outward slope of the flat delta cone obviously 
leads away from the river, the water pouring out through a break in the dike. 
This makes the control of the river, or the repair of a breach in a dike, 
particularly difficult, and gives to the Yellow River outbreaks, spreading side- 
wise, down a delta cone, a character different from those of an ordinary river 
coursing down a valley. 

When a flood makes a complete breach of a dike and escapes in large 
volume to the lower level of the ground outside, it quickly cuts a deep channel 
at the point of exit, which soon may become a gap a mile wide, and it is a 
serious matter to get the river back into its bed, particularly in localities where 
the bed is a few feet higher than the ground outside the dikes. Once in 
each few hundred years it has proved impossible to force the return of the 
river to its previous course, as in 1851-53. It came near to being impossible 
in 1887. 

Remarkable ingenuity and skill, gained from centuries of experience, is 
shown in closing a large breach. In general the method of the Chinese 
engineers, as described to the speaker by Messrs. Charles K. Edmunds and 
F. W. Tyler, the latter a retired sea captain who was for many years in the 
Chinese Coast Inspection Service of the Maritime Customs, is to narrow 
the breach by building out from the two ends with a current-resisting struc¬ 
ture, skillfully made of crossed bundles of large millet stalks (Kao-liang) 
bound with bamboo or straw ropes, pinned down by small stakes, packed with 
river silt, and commonly weighted with more or less loose stone of about 1 
cu. ft. in volume. Meanwhile, short spur-dikes at a slight angle down stream 
are built to deflect the current away from the new work. It is an extraor¬ 
dinary tribute to their skill that by the use of such weak and perishable ma¬ 
terials as Kao-liang stalks and straw ropes, they can narrow the gap to about 
100 yd. after being aided by the subsidence of the flood. This Kao-liang or 
giant millet has a stalk about 6 ft. tall and f in. in diameter, with a thickly 
matted bunch of roots about 5 in. in diameter. It resembles the sorghum 
plant in shape and size. The bunch of roots is placed outward, against the 
impinging current. 

For the final closure, many great ropes of bamboo fiber are stretched 
across the gap, which finally is plugged either by lowering into it, or by 
floating into it, a sort of gigantic thick raft, skillfully built of great bundles 


1134 PROCEEDINGS, AM. SOC. C. E., MAY, 1922 [Papers. 

of millet stalks bound with bamboo ropes and held and guided by perhaps 100 
bamboo cables, each nearly 3 in. in diameter, all constituting an exceedingly 
bold operation. As soon as the current has been thus checked, a thick rein¬ 
forcing embankment of earth and stones is rapidly constructed front and 
rear, by thousands of men with baskets of earth; which next is protected by 
stone rip-rap, and, meanwhile, the river is deflected away from the new em¬ 
bankment by the construction of spur-dikes. 

Some Noteworthy Outbreaks 

By way of further demonstration of the vast importance of finding a 
method of solving China’s flood problems to the many millions of people 
inhabiting this vast delta between Kai-feng, Tientsin, and Chin-kiang (possibly 
more than the total population in the Buffalo-Boston-Washington triangle, 
for the great city populations in New York, Boston, Buffalo, etc., may be out¬ 
numbered in the density of China’s farm population),* the following cases 
of serious floods from outbreak of the Yellow Iiiver are briefly stated. So 
recent is the opening up of that vast country to foreign engineering in¬ 
spection and so imperfect have been the means of transmitting information, 
that the facts have been little known to the outside world. 

The three most noteworthy outbreaks of the Yellow Iiiver in recent years 
of which details are available are as follows: 

First .—The great break of 70 years ago, which changed the river’s course 
for 270 miles, as shown in Fig. 5. This break occurred during the summer 
flood of 1851, but the water seems not to have been completely diverted into 
the new channel until 1853. The new course of this flood laid waste a stretch 
of prosperous country about 10 to 20 miles wide, and about 140 miles long, 
or nearly 2 000 sq. miles, and the escaping waters were not gathered into a 
narrow channel between dikes for this 140 miles below the break until about 
a quarter of a century had passed. No record is now known of the thousands 
of people who perished, or of the great value of the property ruined and the 
fertile farms destroyed along its path. 

This diversion from the course that had been followed for 628 years also 
caused disaster to many thousands of farmers living along the deserted river 
bed by depriving them of their previous water supply. 

Second .—The break of 35 years ago, which cost more than 1 000 000 lives 
and a vast property damage, came near causing a permanent diversion and 
was repaired after 1£ years of mighty efforts and great expenditure. 

Third .—The break of 1903, about 13 miles below Tsi-nan (or “Chinan”), 
which is described by Capt. W. F. Tyler in his pamphletf on the Yellow Iiiver. 
This outbreak deposited a bed of silt said to be from 3 to 8 ft. in thickness, 
over much of an inundated area of about 200 sq. miles, and caused such ter¬ 
rible distress as to call for organization of famine relief from foreign sources. 

Details of the Great Break of 1851 

It is said that foreigners first heard of this break 6 years after it occurred, 
and that 11 more years elapsed before anything definite about the cause of the 


* The speaker has no precise data on this total delta population, 
t Published ip 1906, by the Maritime Customs Office at Shanghai. 




Papers.] 


FLOOD PROBLEMS IN CHINA 


1135 


river s change of course was known to the outside world. The first visit of a 
European to learn what had happened in 1851, was made 17 years after the 
catastrophe, by an English merchant of scientific education, residing at 
Shanghai, Mr. Hey Elias, who visited the new course and the scene of the break 
in October, 1868, and reported his findings to the Royal Geographic Society 
of England, which published his account.* 

For many miles up stream from the site of the former course of the Grand 
Canal, he found the new river flowing irregularly over a strip of country about 
10 or 12 miles in width, which had the appearance of a field, inundated and 
laid waste, rather than that of an ordinary river channel. The strip, thus 
laid waste, probably was 90 miles long. From 20 to 52 miles up stream, from 
the break, the river was flowing in a single, well-defined channel, where the 
shifting currents had deposited low, wide embankments of silt, perhaps 6 to 
10 ft. deep, from which protruded half buried houses and temples. The river 
was flowing between the newly-made banks of silt deposit about 10 ft. high, 
with its bed at about the previous level of the country. Between the hills of 
Yu-shan and Chiau-kou, at the northwest corner of the Shantung Mountains, 
where the escaping waters found and usurped the ancient channel of the Ta- 
ching Ho, the waters were again gathered together and flowed to the sea, 
greatly swelling the volume of the Ta-ching River. Some reports state that 
the silt-laden water raised its deep-cut bed by deposits of silt; other observers, 
including Mr. Elias, reported that the added flow had cut the Ta-ching wider 
and deeper. Probably the discrepancy was due to different localities observed. 
Mr. Elias proceeded down the Ta-ching Ho to where it entered the sea to learn 
of its possible availability for navigation. The lower 20 miles was found 
to be flowing through low uninhabited mud flats, deposited from the river’s 
burden of silt. The report by Mr. Elias is an admirably clear description, 
which impresses one with the author’s keenness as an observer. 

Mr. Elias made a second visit for the purpose of exploring a new con¬ 
nection said to have been established in 1868, between the Yellow River and 
the Yang-tze via the Sha Ho and Huai River, through a break in the south 
dike 50 miles up stream from the City of Kai-feng. He found, however, that 
the breach had been repaired and that boat navigation was stopped early in 
1870, after more than a year of flow through a breach 1 mile wide, but not 
deep. Mr. Elias, in his second paper, discusses the merits of turning the 
Yellow River back into the course it had followed prior to 1851, and calls 
attention to the great hardship that had been suffered by the large population 
along the old course of the river, in being deprived of water for irrigation 
and navigation.- A large migration of this river thus brings disaster to 
millions of people along both the old and the new courses, because this fertile 
delta is populated in many places so densely that a farm of 3 to 5 acres has 
to provide the support of a family. 

About ten years later, the new course was visited by a prominent English 
engineer, Mr. G. J. Morrison, who made an outline survey and map. The 
multitude of shallow shifting irregular streams flooding 10 to 15 miles in 
width, found by Mr. Elias, had then been gathered into a single stream between 


* Journal, Royal Geographic Soc., Vol. XL (May 5th, 1871). 



-ECTioNS of dikes Site of great outbreak of vellow River and change of Course in issi 

All dimensions in Meters FROM Reconnaissance anO Levels of Grand Canal Impt- Bb 19>9 

Contours in Meters above Tsing'-Tau Datum 


1136 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers. 






















































































































Papers. ] 


FLOOD PROBLEMS IN CHINA 


1137 


dikes, or had gathered itself, into this single, narrow channel by its erosion of 
its bed slightly below the general level of the plain as now found and shown 
in the top sections of Fig. 12. 

An outline map of the region near the break of 1851, surveyed early in 1919, 
is given in Fig. 14. The speaker visited this locality in December, 1919, and 
found the landscape so broad and of such low relief that it was difficult for 
one in the field to take in the relation of one part to another. Although the 
chief events are plain, it will require a much closer and more detailed topo¬ 
graphic map than is yet available, and a week in the field, map in hand, for 
tracing out in detail just what happened where the river changed its course. 
The river, breaking out to the north, found a country about 12 ft. lower in 
elevation than its former bed, over which it could flow, and over this, in ill- 
defined shifting channels the flood ultimately reached the Valley of the Ta- 
ching Ho, within which, the records show, it had flowed about six centuries 
before, for at least about 80 miles, perhaps then reaching the sea by the Hsiao- 
ching Ho, instead of by it^ present course. 

As stated previously, the escaping flood of 1851 usurped this Ta-ching 
channel and in the course of 50 years, filled some miles in length of its bed 
with silt almost to the general level of the ancient delta plain, the depth of new 
silt thus deposited at Lo-kou being about 12 ft., according to borings made 
for the railroad bridge. Possibly, the “Ta-ching” or “clear-water” river, which, 
although small, sometimes gives brief violent floods, by six centuries of effort 
had scoured this part of the channel bed below the elevation that it pos¬ 
sessed when occupied by the Yellow River from 1194 to 1289. 

Some Details of the Flood of 1887 

The outbreak of 1887, already mentioned, has been described by the English 
engineer, G. J. Morrison.* He says, “the breach through the dike was a full 
mile in width and the flood swept onward toward Hun-tze Lake and the Huai 
River, inundating a strip variously estimated at 20 to 50 miles in width, 
carrying away houses and villages and parts of walled cities.” 

Mr. Morrison reports that the breach occurred on September 29th, 1887, 
but was so great that it had not been closed when the next year’s flood came 
in June, earlier than expected. All repair work of the previous months, which 
had cost a vast sum, was wasted, but the Chinese began resolutely again and, 
declining to follow foreign advice, adhered to their own ancient methods. At 
the time of his visit (September 1st, 1888), they had narrowed the gap to 400 
ft. through which flowed an eddying current of about 7 miles per hour (10 ft. 
per sec.). He concluded that the original bed of the river was about 4 ft. 
higher than the level of the plain outside. The flood surface, of course, was 
much higher. His soundings showed a depth of 60 to 70 ft. in the breach and 
a deep gully for some distance inside and outside. 

Mr. Morrison reports further, that the new banks were faced with Kao-liang 
stalks firmly packed in earth and that these millet stalks were brought, in 
some cases, by wheelbarrows from farms 20 miles away and that the earth for 
the new dike was all brought in baskets. 

* Engineering (London), March 3d, 1893. 



1138 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers. 


The final closure was made by a mattress of Kao-liang stalks and earth 
thoroughly bound together, suspended from many great bamboo fiber ropes 
across the breach, and lowered into place. The closure was completed on 
February 2d, 1889, and was greatly aided by a low stage of the river and by 
a strong ice cover. 

Fig. 15 shows the interior of a temple that celebrates the closure of the 
break of 1887. Gordon Gumming* describes this flood as covering a strip 30 
miles wide, having an area of 10 000 sq. miles, and flooding or destroying 3 000 
large villages, with a probable loss of life of 7 000 000; and states that the flood 
continued high for two months and that the Chinese Imperial Treasury 
donated $2 500 000 for relief. 

The speaker visited the site in December, 1919, and he has profound respect 
for the skill that under such difficulties could achieve success with such poor 
structural materials, such simple tools, and nothing but non-cohesive, fine 
sand with which to build this vast thick dike 30 ft. above the plain. Fig. 10 
shows the site as the speaker found it, looking outside the dike across the 
gully of the flood. 


Some Details of the Flood of 1902 

Some features of the outbreak of 1902-03, on the lower river, are given in 
Capt. Tyler’s report on the Yellow River, mentioned elsewhere in this paper, 
and some of the chief items of interest have been quoted, previously. The 
breach occurred on September 12th, 1902, near the end of 2 months of flood 
and continued 6 months and 4 days. An attempt at closure on January 2d, 
1903, soon after the flood had subsided, was frustrated by the capsizing of the 
mattress raft with which it was planned to close the final gap. Capt. Tyler 
states that in damage, maintenance, and expense of closing this breach, the 
Yellow River cost Shantung Province $2 000 000 in 1902. He attempted an 
estimate of the vast volume of silt deposited, after observing a few localities 
and seeking information from the natives regarding the other localities. He 
concluded that an average depth of 3 ft. over the 200 sq. miles might perhaps 
be true. A 3-ft. depth on 200 sq. miles would be about 400 000 acre-ft., a 
quantity so vast that the speaker cannot quite credit it after computing the 
probable discharge of water and its probable proportion of silt, carried at 
various stages, and considering that the outflow was mostly after the flood 
had largely subsided. 

The colored illustrations of Kao-liang dike protection and groynes in the 
little book by Capt. Tyler,f are the finest that the speaker has ever seen. The 
book contains many interesting and valuable data regarding the Yellow River 
between Lo-kou and the sea. By sounding, Capt. Tyler found a maximum 
depth of 40 ft. in the channel pools in the low-water season and in some places 
a depth as great as 30 ft. against the bank, with slopes of 45%, of partly decom¬ 
posed Kao-liang, to which he recommended that a facing of rip-rap be applied 
as providing the most efficient and economical maintenance. His chief recom- 


* “The Leisure Hour”, pub. about 1888. 

t “Notes on the Yellow River”, pub. by the Imperial Maritime Customs, Shanghai, 1906. 



Papers.] 


FLOOD PROBLEMS IN CHINA 


1139 






Pkj !5._interior of Chinese Temple Which Commemorates Closure of Break of 

Flood of 1887. 









1140 PROCEEDINGS, AM. SOC. C. E., MAY, 1922 [Papers. 

mendation was that the low-water channel be straightened by groynes and 
by silting in the eddies below the groynes, and that the erosive power of the 
river at all seasons, should be thus prevented from acting on the main dikes. 
He also suggested a system of temporary detention reservoirs along the river 
in the upper part of the delta, in which flood water might be detained and silt 
impounded for raising the general elevation of the ground. 

Capt. Tyler states that he has recently found to be unreliable some of the 
information given him in 1902 as to the rate of the filling up of the Ta-ching 
Ho since the incursion of the Yellow River, which he quoted in this report 
of 1906. The actual filling is much less. He gives much other interesting 
general information of the Yellow River down stream from the crossing of the 
Tientsin-Pukow Railroad. About 30 years after the incursion of the Yellow 
River, and after the bed of the old Ta-ching Channel had become more or less 
raised, dikes were built from 3 to 7 miles apart, enclosing the enlarged river. 
Later, the riparian farmers, desiring, to reclaim the land, were permitted to 
build, without much system or control, inner dikes only about a mile apart. 
These dikes, in the course of time, became the main dikes and the outer dikes 
were neglected. The river floods now rise about 15 ft. above the general delta 
level and are restrained by the inner dikes. 

Floods Along the New Course 

Down stream from the outbreak of 1851, along the new course, as far as 
the confluence of the Ta-ching Ho, the surface of the Yellow River, when 
not in flood, is not elevated above the surrounding country, as has been previ¬ 
ously stated and as is shown by sections at the top of Fig. 12. The outbreak 
of 1919, shown by Fig. 13, is of interest in illustrating the small danger of a 
permanent outbreak in that part of the river the bed of which is not elevated 
above the surrounding country, and in showing the efficacy of the outer dike. 
Nevertheless, this particular flood is reported by local magistrates to have 
spoiled the crops on 125 sq. miles, surrounded 560 small villages, drove out 
217 000 people, and destroyed property worth $350 000. 

In this case the inner dike probably had been neglected, a gap having been 
worn in the road across the top was found by the rapidly rising flood which 
was higher than any of the preceding ten years. The outrush of water cut a 
deep channel at the point of exit and then spread in a broad thin sheet, flowing 
southward, ruining growing crops on the intensively cultivated little farms, 
until intercepted about 8 miles away by the south outer dike, along which it 
flowed about 20 miles parallel with the main stream, until caught in an angle 
between dikes, where, by reason of the inner, or river, dike being lower than 
the cross-dike, the flood broke its way back into the main channel. 

Fig. 13 shows some typical channels, in which it appears that the water 
tends to gather itself by means of its power to erode the soil and carry it in 
suspension; but the general effect of these outbreaks is to spread a broad 
stratum of sediment over nearly all the country inundated. 

A peculiarity of the Yellow River sediment is its remarkably rapid and 
almost complete subsidence in still or slow moving water, therefore this 


Papers.] 


FLOOD PROBLEMS IN CHINA 


1141 


stratum is thin under the pools farthest removed. Care was taken to measure 
the depths at many places and the results are shown in typical places on the 
map. In general, the depth over the local surface was about 1 in. and along 
the gullies about 1 ft. A rough estimate gave a total volume of about 
12 000 acre-ft. of sediment deposited on about 60 000 acres. The Chinese 
engineer who made this reconnaissance, found difficulty in measuring the 
precise depth of sediment and, obviously, saw only a small part of the sub¬ 
merged 125 sq. miles in his rapid trip around the edges and down the gullies; 
the figures, therefore, on Fig. 13, are to be considered illustrative and not as 
a definite measure of the whole. The average depth was only one-fifteenth 
of that reported by Capt. Tyler from the outbreak of 1902, notwithstanding 
the water at the time of this 1919 break was carrying, by weight, about 4% 
of sediment; but here, in 1919, only a small portion, perhaps 20%, escaped 
from the main channel and this stopped flowing as soon as the river stage fell 
below the level of the country; whereas, in 1902, the whole river broke out, 
and continued out of its channel for six months. These two divergent 
instances are quoted to illustrate that one must not be hasty in generalizing 
about silt deposits from outbreaks until all the facts are known. 

Ancient Records 

A research among the city, provincial, and National records, probably would 
give a story of hundreds of outbreaks and show that at one place or another 
along this 400 miles of the Yellow River’s course, for several thousand years, 
the population far and wide over this vast delta has lived in great danger, 
which danger exists to-day. 

To illustrate the care with which the Chinese keep records in even the 
smaller towns: At the little Town of Lan-yi, near the great break of 1851, the 
speaker asked the magistrate about previous breaks, and a few hours later he 
had reviewed the town records for the preceding 200 years and presented a 
concise statement of about a dozen important floods or outbreaks in that 
immediate vicinity. 

* 

The Finje Report on the Yellow River 

Because of the heavy floods in the Yellow River delta in the autumn of 1887, 
a reconnaissance was made in 1889 of the Yellow River through the delta, at 
the request of the Imperial Government, by two Dutch engineers, Yon Scherm- 
beck and Yisser, and under the general counsel of Mr. Finje von Salverda, 
an eminent Dutch authority on rivers and harbors. Mr. Finje did not himself 
visit China, but wrote a sixty-page introduction, comprising many observations 
by Richthofen and sundry philosophical discussions. The interesting report 
by his agents adds little precise information to that given by Elias and Mor¬ 
rison, but confirms their statements. Messrs. Visser and Yon Schermbeck 
express opinions favorable to training the river, and state that a limiting of 
width might be advisable, noting that at Tsi Ho, a few miles above Lo-kou, the 
river got along very well in a channel only 1 770 ft. wide. They agree with 


1142 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers. 


Mr. Morrison that, at the break of 1887, the bottom of the Yellow River 
originally was about 3 to 5 ft. higher than the ground outside the dikes. They 
record their observation, which is confirmed by the speaker’s surveys, that “the 
whole of the new course from the great breach of 1852, appears to be below the 
general level of the country immediately adjacent to the river” and list sixteen 
outbreaks through the Yellow River dikes in 16 years in Shantung and Chihli, 
which affect Shantung Province. 

Past and Present Safeguards against Yellow River Floods 

From time immemorial, the maintenance of the Yellow River dikes has 
been one of the principal functions of the Government of each Province. 
Capt. Tyler states that until 1901 the whole river was in charge of one office,- 
the River Viceroy, and that since then each Provincial Chief is responsible 
for the section of river within his Province. The conditions and methods 
described by Capt. Tyler doubtless prevail largely to-day. In Shantung, in 
1903, he found three river Taotais controlling, respectively, the upper, middle, 
and lower thirds, and each Taotai had under him six military captains who 
were practically the resident engineers. Taotais and captains had been 
brought up from youth on this river work, and he met several who had been 
employed on it for 50 years, and who remembered conditions along the Ta- 
ching Ho prior to the invasion of its bed by the Yellow River, earnest, careful 
men eager for new ideas, but extremely conservative in following ancient 
practice. Each captain had charge of only one side of the river. In pro¬ 
tecting his bank, if he deflected the river against the opposite bank, that was 
the affair of the opposite captain. The speaker presumes that the care given 
under the Imperial System may have relaxed in some sections, with the dis¬ 
turbed political conditions of recent years. 

In 1903,* Capt. Tyler estimated the expenditures on the Yellow River at 
3 500 000 taels annually, equivalent to about $2 500 000. lie estimated the 
annual destruction of property by the river’s floods at about $1000 000, 
without including the great catastrophes of 1851 and 1887. 

Capt. Tyler’s report gives an interesting account of current practice on the 
lower river down stream from the Tientsin-Pukow Railroad in 1903, showing 
forms of shore protection and a method of closing a break. The groynes 
shown by him are constructed from Kao-liang, or millet, stalks, but their 
purpose is the same as that of the stone groyne shown in Fig. 8. The shore 
protection, that the natives call the “fish-scale” type, is built also of millet 
stalks, tied, pinned, and packed together with earth tamped into the interstices. 
The “fish-scale” or serrated form of Kao-liang bank protection is considered by 
Tyler as a deliberate design, in preference to a smooth face, and that this 
preference is based on experience with this perishable material, which has a 
stalk about 6 ft. tall, that is weak and composed mostly of pith, but which has a 
mat of firm strong roots that are placed outward in the embankment to receive 
the impact of the current. In course of a year or two, the Kao-liang rots as the 
river rises and falls and a “pakwerk”, 25 ft. high, may settle 4 to 8 ft. As long 

* “Notes on the Yellow River”, p. 10, Shanghai, 1906. 



Papers.] 


FLOOD PROBLEMS IN CHINA 


1143 


as the river persists in its attack on this particular piece of bank the protection 
of Kao-liang is renewed by placing more on at the top. The mat of Kao-liang 
that is settled and compressed below the low-water level may last a long time. 
In many places, the Kao-liang groyne is faced later with a rip-rap of stones 
averaging 1 to 2 cu. ft. in volume. 

No protection works face the earthen main dike, except where the river now 
impinges, or where in former years it has attempted to cut through. 

The Yellow River Digs Deeply in Floods 

The remarkable erosive action on the bed of the Yellow River and the vast 
quantity of the fine-grained silt that this river can carry in a day are “great 
forces of Nature” that the speaker would propose to “use for the benefit and 
convenience of man,” thus fulfilling the traditions of Civil Engineering as 
defined by Tredgold in the charter of the Institution of Civil Engineers of 
Great Britain. 

In the course of investigations on the channel of the Yellow River* 
preliminary to designing its crossing by the Grand Canal, it has been found 
that, during a flood, this river digs its channel deeper and wider in a most 
remarkable way, and thereby gains at the bottom of the normal river bed 
much of the additional area of cross-section required by the enlarged volume. 

As the flood subsides, silt is deposited, refilling the channel and raising the 
bed to its former elevation and contour. The speaker was on the lookout for 
this phenomenon, because years ago his attention had been called by Horace 
Ropes, M. Am. Soc. C. E., to a similar phenomenon in certain rivers of New 
Mexico and Arizona; also similar erosion and refill had been observed on the 
Colorado at Yuma, Ariz., which the speaker had visited and which at that 
point and below greatly resembles the Yellow River in its silt burden. 

Similar erosion and refill also has been noted by English bridge engineers 
on certain rivers in India, but in none of these cases previously published have 
the observations been so extensive in following the changes through the rise 
and fall of a flood, or so carefully confirmed at every stage, as in these measure¬ 
ments of velocity, depth, and silt burden, made at four stations along the 
Yellow River many miles apart. 

This fact of the readiness of the Yellow River to scour a deeper channel 
when properly confined between dikes, taken in connection with the prac¬ 
tically unlimited depth of the bed of silt in which it can dig, together with the 
hydraulic law of increase of velocity with increase of depth, makes it feasible 
to maintain a narrow channel at all stages from drought to flood, that can 
quickly adjust itself to carry a large volume of flood water. Before discussing 
the training of the river in a new straight channel, however, the proof of the 
facts about erosion and refill will be presented. 

For frequently measuring the depth, width, velocity, and discharge of the 
Yellow River, gauging stations were established by the Grand Canal Improve¬ 
ment Board, in 1918-19, at the following places: 

* The speaker has in preparation a paper on the “Hydraulics of the Yellow River” in 
which the characteristics of this stream are discussed in greater detail than space permits 
in this paper. 




1144 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers 
























































































































































































































































Papers.] 


FLOOD PROBLEMS IN CHINA 


1145 


(1) Near the ancient canal line at Shih-chia-wa. 

(2) At a possible site for a new crossing at Wei-chia-shan, 13 miles 

farther down stream. 

(3) At another site for canal crossing, 6 miles farther down stream, at 

Chian-kou opposite to Yu-Shan. 

At each of these places, systematic current-meter gaugings and soundings 
were made from the low-water stage in the spring through the various rising 
and falling stages of a flood greater than any of the preceding ten years and 
extending into the autumn when the river had nearly fallen to its normal 
stage. 



(4) Meanwhile, the Chihli Eiver Commission established frequent 

gaugings at the bridge of the Tientsin-Pukow Eailroad about 70 
miles down stream from Chian-kou. 

(5) A station, about 300 miles up stream from Station No. 1, within 

the hilly country up stream from the delta, was also established by 
the Chihli Eiver Commission for obtaining a rating curve for a 
cross-section where the bottom of the river was supposed to be 
stable, hard, and not subject to scour. 

These several cross-sections were purposely selected as having different 
characteristics of outline and velocity of approach, with a view to using each 
as a check on the other and to guard against being misled by abnormal con¬ 
ditions at any one location. 

The results of soundings and gaugings at all four locations confirmed one 
another in a most satisfactory way. The more important results for two of 
























































































































1146 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


L Papers. 


these stations are shown in Figs. 16 and 17, in which, for clearness there have 
been plotted only a few typical cross-section lines for different stages. In every 
case, as the discharge increased, the river dug its bed enough deeper and wider 
so that with the rise and spread at the top, the mean velocity of the whole 
cross-section never rose above about 24 m. (or about 8 ft.) per sec. As the 
flood subsided, the space thus excavated was refilled with a most remarkable 
constancy of relation. 

In many other gaugings of streams within the China delta plain, the speaker 
has found that the mean velocity of the entire cross-section seldom rises to more 
than 6 or 8 ft. per sec., in floods. In other words, given a material that can be 
eroded, the current digs out the bed and carries off the excavated material in 
suspension, until it has made for itself a comfortable channel in which it 
does not have to hurry. 

Some careful tests were made for finding the truth about the oft-quoted 
statement that near the bottom of this and other streams heavily laden with 
silt, there is a flowing stream of soft, semi-fluid mud 1 ft. or more in thickness. 

The silt sampling by means of pump and pipe immersed at various depths 
showed nothing of that kind, but in order to be sure about it the speaker had 
special tests made at several points near mid-channel under the Lo-kou Bridge 
of the Tientsin-Pukow Railroad, with a horizontal flat iron disk, 14 in. in 
diameter, screwed to the bottom of a long vertical iron pipe about 1 in. in 
diameter, which reached above water and was used as a sounding rod, and 
manipulated from a boat held in position by ropes from the bridge. Within 
this iron pipe was a 4-in. steel rod sliding up and down, projecting above the 
top of the pipe, which could be thrust several feet into the river bottom by 
applying the weight of the observer. The observer could feel the consistency 
and hardness of the river bed plainly with the disk and rod, and many trials 
showed it about as firm and sharply defined in mid-channel as in depths of 2 
or 3 ft. near the shore. The existence of a flowing bottom stratum of semi-fluid 
mud was disproved. 

Soundings were also made with a thin wire line and flat-bottomed, boat¬ 
shaped lead weights, capable of combination to give 30, 60, 90, and 120 lb. 
weight in air. The elevation of the river bottom determined by the heaviest 
weight was not materially different from that determined by the lightest 
weight, or from the depth measured by the disk and stiff sounding rod; all of 
which confirms the speaker in the belief that the depths measured in Figs. 16 
and 17 are dependable and that there was, in general, no serious error or excess 
from the bellying out of the sounding line in the swift flood current. 

The silt content that can be carried in the water of the Yellow River within 
the delta region is found to be closely related to the mean velocity. As the 
velocity increases beyond, say, 2 or 3 ft. per sec., more silt is taken from the 
bed into suspension, but it is dropped promptly when the mean velocity 
decreases. This is illustrated in Fig. 18, in which are given lines showing the 
daily height of the water, the rate of discharge, the percentage of silt by weight, 
and the mean elevation of the river bed for a width of about 200 ft. near mid¬ 
channel, each of these lines being a composite made up from the measurements 
at the three principal gauging stations, all of which were in excellent general 
agreement. 


Papers.] 


FLOOD PROBLEMS IN CHINA 


1147 


It will be noted that there is a lag of from 7 to 10 days from the discharge 
curve to the line showing the erosion and refill of the bed. It would be inter¬ 
esting to have similar curves from gauging stations located, respectively, near 
the up-stream and near the down-stream end of the channel through the delta, 
or > say, 250 miles apart, for observing the influence of the quantity of silt 



10 


_ rC 

8 .bp 
"5> 

7^ 

XJ 

6 c 

6 I 

9 
4 W 

< 4 H 


* c 
a> 

,o 

1 u 
<u 
Pk 


taken into suspension from this erosion day by day, or week by week. All 
of the speaker’s observations tended to show that this silt picked up along the 
way, forms only a small part of the entire silt burden brought down through 
the delta from the erosion of the vast loess hills of Shansi and other Provinces 
far up stream. 







































































































































































































1148 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers. 


A study of this phenomenon, excavation and refill of the river bed as velocity 
rises and falls, which will be presented later in more detail in the speaker’s 
proposed paper on the hydrography of the Yellow River, points the way to 
a successful training of this river by compelling it to dig and maintain 
its own flood channel and to carry its burden of silt to the sea. Many 
recent hydraulic investigations concur in showing that with increase of 
depth, velocity increases in a much larger ratio than that given by the Chezy 
formula which makes the increase proportional to the one-half power of the 
depth, whereas the newer formulas make it as the two-thirds or even the three- 
fourths power. This larger ratio is on the right side to be helpful in the 
present problem. 


Characteristics of Yellow River Silt 

The feature of special interest shown in Fig. 18, is the facility with which 
increased mean velocity was found to pick up an increased burden of silt 
and carry it along. The normal silt burden at the low-water stage averages 
about 0.4% by weight. After mean velocities of from 5 to 8 ft. per sec. had 
continued from 1 to 3 weeks, the silt burdens gradually increased to an 
average of 6.5% by weight, corresponding to 4.5% by volume as deposited on a 
compact bank. This 6.5% was found as the mean of eighteen samples taken 
at six widely different localities from July 31st to September 2d, 1919, during 
the high<flooa\of thqjtfrateft; at the peak, the load was 9 or 10 per cent. The lag 
in picking up the full silt burden is very noticeable and indicates that a 
relatively small part of this is picked up locally from the bed, and that a large 
part may come from the action of the flood on the loess hills far up stream. 

When one calculates these percentages of suspended silt, averaging upward 
of 5% for 40 days, into an average flood discharge of 150 000 sec-ft., the number 
of cubic yards of excavation transported per day or per month by the swiftly 
moving water, amounts to vast quantities in comparison with what man could 
afford to do by dredges or steam shovels. When one extends the computation 
to cover all the material transported by this entire flood of 1919, the volume 
becomes too great for one to believe that the silt movement always has gone 
on at this rate, year after year, through ten or twenty centuries. The shore 
line has moved seaward a long distance in the past 2 000 years, but hardly 
enough to cover such vast quantities. Pumpelly and Von Schermbeck and 
Visser cite a few localities and records, indicating a progress of the shore line 
seaward about 100 ft. per year, or about 1 mile in a century. 

One should not generalize too far about the total annual volume of silt 
carried to the sea, until similar observations have been continued through the 
floods of several years. It is conceivable that somewhere in the loess hills of 
Shansi some particular cliff may have been cut into at an abnormal rate during 
this particular flood of 1919, or that something abnormal was going on during 
the outflow of 1902, which left the vast deposits described by Capt. Tyler. 

Many hundreds of samples of this silt from the Yellow River and other 
streams along the Canal were collected, in 1919, at different flood stages, by 
subsidence from measured volumes of water and evaporation to dryness. Many 
other specimens were obtained by cutting out solid blocks from the river mar- 


Papers.] 


FLOOD PROBLEMS IN CHINA 


1149 


gins. The average of many specimens from many localities carefully collected 
and evaporated to dryness at 240° Fahr., showed for a densely compacted 
oven-dried cake a weight of 110 lb. per cu. ft. of final size as the 
maximum, and the ordinary oven-dried specimen weighed about 90 lb. per cu. 
ft. of original size as cut from the bank. Blocks with their natural water con¬ 
tent as taken from a well settled bank along the river, averaged about 120 lb. 
per cu. ft. 

In nearly all samples, the grains of this sand are of such microscopic size 
that 99% of the whole would go through a cement test sieve having 200 
meshes per lin. in. The speaker examined many samples from widely distant 
localities, under a microscope with a power of 100 diameters. All these 
samples presented much the appearance of good mortar sand when thus 
magnified, and by measurement with an eyepiece micrometer, the diameter of 
nearly all the particles was less than 0.001 in., although a considerable per¬ 
centage were only about one-tenth of this size. In spite of these extremely 
small dimensions, very little colloidal or adhesive quality was found, and 
nearly all the material in suspension in a glass of the turbid river water, 10 
in. tall, would settle to the bottom within 15 min., leaving the water above with 
only a slight opalescence and so clear that fine print could be read through a 
column several inches in thickness. 

This remarkably prompt subsidence has an important practical bearing on 
training the river so that material excavated in one place may be laid down 
in another place as desired by giving the silt-charged water a quiet pool in 
which to lay down its load. 

This silt comes from vast deposits of loess in Shansi and other Provinces 
up stream, the most extensive in the world. In some places, these deposits are 
said to be more than 1 000 ft. thick. Where the speaker examined the loess 
hills, or the edge of the plateau, near the Peking-Hankow Railroad Bridge, 
the loess rises 225 ft. above the river, in steep bluffs, cut deep by small streams 
during heavy rains. In situ loess is a peculiar material and can stand 
in a bank with a vertical face many feet high; it cuts, smoothly, like cheese, 
absorbs water readily, and “dissolves” rapidly in a stream. 

That sometimes the river carries sediment of much coarser grain, a true 
sand with grains averaging, say, in. in diameter, is shown by sand dunes 
outside the banks near the break of 1851, by dunes along the south dike up 
stream from the break of 1887, by vast fields of drifting sand along the Lung- 
Hai Railroad, and by drifts high against the eastern city wall of Kai-feng. 
Apparently, 99% of all the earth seen by the speaker along the Yellow River 
delta was of the fine-grain variety, of loess origin. 

As the speaker cruised down the river in a small boat, he gave much atten¬ 
tion to the ever-changing contour of sand-bars and shores and to the varying 
depths over the sand waves of the bed, frequently prodding the bed with a 
sounding pole and always finding the bottom yielding, but well defined. The 
standing waves in the surface of the water in many places gave evidence of 
sand waves, forming and slowly moving along the river bed. The low-water 
channel is extremely unstable. 


1150 PROCEEDINGS, AM. SOC. C. E., MAY, 1922 [Papers. 

Applications to River Training and Flood Relief 

The preceding particulars have been given in some detail because of the 
possible wide application of the principles of river-bed erosion and re-fill to 
river training. From superficial observations in several other delta regions 
in China, the speaker is inclined to believe that a thorough investigation 
would reveal similar relations of velocity to scour of bed and its re-fill at 
several localities where flood channels are needed, and that the methods to be 
described for training the Yellow River could be made of wide application 
in China; but before laying out or beginning the construction of extensive 
works, he would, as a matter of course, insist on surveys, borings, test pits, 
and a variety of tests of physical qualities at the locality where these methods 
are to be tried, all made with great care and under competent direction. 

One cannot yet be sure that all this silt of the great northeastern delta 
plain of China presents these characteristics found along the present course 
of the Yellow River between Shi-Chia-Wa and Lo-kou. Moreover, the speaker 
has read reports of investigations of silt from beds of smaller streams near 
Shanghai, which at moderate depths seem to present more of adhesive quality 
in the river bed and which might resist erosion. 

The colloidal qualities of river-bed clays and silts and the causes of 
remarkable differences in adhesion, plasticity, and colloidal suspension are 
matters within the profound depths of molecular physics, which are only now 
beginning to receive the investigation that is merited by their practical 
importance in engineering operations. 

A River-Training Laboratory 

At present, there is only one laboratory in the world, as far as the speaker 
knows, designed for the special study of river-training problems. This is the 
Fluss-Bau Laboratorium at the Dresden Polytechnikum. In 1913, the speaker 
visited the old and the new laboratories at Dresden, and Professor Engels who 
is in charge, has courteously sent him accounts of some of his recent experi¬ 
ments therein, illustrating the formation of sand-bars and pools and the effect 
of groynes of various shapes and inclinations on scour and deposit at various 
velocities. Apparatus of this kind, but on a larger scale, is needed, both in 
America and in China, for a wide range of experiments on river training, and 
the speaker has told some of the Chinese statesmen that in skillful hands it 
might pay dividends of 1000% per year on its cost, in their river and harbor 
problems. He would recommend working out the best means of channel 
training and the best shape of groyne for the Yellow River by trial-and-error 
methods, conducting experiments on a full-sized structure in the river almost 
simultaneously with experiments on the laboratory model, and thus seek to 
develop the precise form of the improvements in a tentative way, step by step; 
but he would follow the ancient Chinese practice of dike and groyne as far 
as possible, until it appeared certain that better methods and types had been 
developed. 


Papers.] 


FLOOD PROBLEMS IN CHINA 


1151 


A program could readily be planned, under which this careful proving up 
on designs during the necessary time for surveys need not delay the prompt 
and rapid carrying out of the sorely needed works of flood protection or 
flood prevention, along the Yellow River, the Wei or Hai River and the 
Hwai River, or wherever funds are available. 

Protection Against Floods 
A Possible Method of River Training 

The chief object in the river training now proposed is protection against 
floods by ultimately forming a thick, flood-proof dike by means of silting up 
the space between the present inner dike and a new straight dike built to confine 
the new straight and narrow channel and hold this from meandering, so that 
it will henceforth flow everywhere between new banks protected against under¬ 
cutting by spur-dikes, somewhat as shown in Fig. 19. 

All things considered, the Chinese have done wonderfully well in their 
river training by the methods they have followed for hundreds, and perhaps 
thousands, of years; but it should be possible to make great improvements by 
means of precise scientific observation and by slow painstaking study in 
laboratory and field with modern instruments and methods. The facts already 
observed have convinced the speaker that it is possible to utilize some of 
these marvellous forces of Nature found in the erosion and transportation 
of silt, to perform much of the labor of building and maintaining the channels 
and embankments needed for protection against the outbreak of floods. 

In illustrating what the speaker now has in mind, he desires first to make 
it plain that the forms and dimensions shown in the following drawings may 
need to be modified after further observation and study in the field and study 
in a hydraulic laboratory. With this reservation, the speaker presents the 
outline design, shown in Fig. 20. 

The river would be compelled to flow in straight courses, 5, 10, or 20 miles 
in length, laid out nearly midway between the present inner dikes, as may 
best fit existing conditions in different localities, somewhat as shown in Fig. 6 
by the parallel straight lines. 

The new flood channel would be made only about £ mile in width at the 
surface, the centers of the new main dikes being less than i mile apart, instead 
of from 4 to 8 miles, as at present. 

Various means in different localities would be used to swing the river into 
the new straight channel, utilizing the natural erosive power of the current to 
the greatest practicable extent and building out long spur-dikes to turn the 
current toward the new channel the opposite dike of which would have been 
previously built and provided with groynes, lest the current overshoot the 
mark. 

The space of from 2 to 3 miles in width thus left between the old inner 
dike and the new straight dike, as shown in Fig. 19, would ultimately become 
silted up to nearly the level of ordinary floods, forming the most fertile kind 
of agricultural land, like the rich bottom-lands, or intervales of American rivers, 


1152 


PROCEEDINGS, AM. SOC. C. E., 


MAY, 1922 


[Papers. 



tfi r+ 












































































Papers.] 


FLOOD PROBLEMS IN CHINA 


1153 


but presenting the great superiority of having the admission of flood water 
always controlled until growing crops had been harvested, by substantial sluice¬ 
ways and gates built into the new dikes. After the crop had been harvested, 
the occasional admission of more or less flood water would add to the fertility 
and aid the maintenance of a deep-seated reserve of moisture in the subsoil. 
It is obvious that when this broad terrace of earth between the old dike and 
the new dike has become built up to about the level of ordinary floods, if 
subsequently the inner dike becomes overtopped by an unprecedentedly high 
flood or undercut by the current under extraordinary conditions, this barrier 
of elevated ground about 2 miles in width in front of the old dike, would 
prevent any rapid outrush of water from causing disasters like those of 1887 
and 1851, or the countless series of outbreaks that have occurred from time 
immemorial all along the course of the river through the delta. 



The speaker would make each necessary change of direction between these 
long straight reaches of new channel by means of a relatively short sharp 
curve of a radius only two or three times the channel width. At present, he 
attaches little importance to the theory often mentioned in papers on river 
training that because rivers naturally flow on curves and not on straight lines, 
therefore, a gently curving course is the best in which to train a river. Nature’s 
chief object in the winding course of rivers seems to be delta building and 
the distribution of sediments eroded and brought down from the hills; 
whereas, on the contrary, the object of man in this case and many others is 
to prevent meandering and bank-cutting and to cause the river to carry its 
burden of silt in the flood water to the sea in the most direct and certain 
way possible. It is not believed that the interests of future navigation of 
the Yellow River would be sacrificed by these straight courses, or that, as a 
whole, the river dikes would be more difficult to maintain. 

Since this paper is primarily on “Flood Problems”, the speaker will 
deal only briefly here on the hydraulic problems, leaving their discussion for 
another paper already mentioned, that he has in preparation. 

Although flood protection is the controlling motive, navigation must not 
be forgotten. At present the navigation of the Yellow River is confined to a 
multitude of small boats of about 3 or 4-ft. draft, 10 ft. wide, and about 40 
to 50 ft. long. The shoals are many and capricious. It seems certain that 
the new, confined and deepened channel would bring great improvement over 
present conditions. 











1154 PROCEEDINGS, AM. SOC. C. E., MAY, 1922 [Papers. 

As to possible troubles from hills and hollows, or shoals and pools, in the 
river bottom, caused by the alternate obstruction at the groynes and the 
enlargement and eddying below the groynes, the speaker was encouraged to 
believe that a satisfactory condition could be worked out, by his observations 
of the currents, shoals, and eddies at the old Chinese groynes along this 
river, during his cruise between the railway bridges in December, 1919. 
Nevertheless, he would propose a careful study of the best spacing for groynes 
by laboratory models, before building many structures in the field, and would 
take long and careful counsel from the most experienced Chinese conservancy 
superintendents, and would carefully study the sand waves in the bed, of 
which he noted many examples as he cruised down the river. 

The long continued and almost general use of the spur-dike by the 
Chinese for turning an impinging current away from a dike built of soft, 
easily eroded earth naturally calls attention to that type of construction, as 
having been proved by centuries of experience to be well adapted for meeting 
local conditions. Moreover, it takes little arithmetic to show that a smaller 
quantity of stone rip-rap will be required for protecting a mile of river 
bank when this is carefully and scientifically disposed in spur-dikes than 
if placed in a continuous line of rip-rap parallel with the shore. Also, 
any sudden freak of the river in threatening the dikes at a particular point 
can be most quickly warded off, with a smaller quantity of stone and by fewer 
men, when the material is dumped off the end of a narrow spur-dike. 

In brief, although the speaker has confidence in the general method herein 
proposed, he would at first build only 2 or 3 miles of new channel with the new 
shape of dike and groyne, and study its behavior and expect to improve the 
details. Meanwhile, he would seek maximum economy through painstaking 
observation, experiment, and the counsel of others, and then proceed with 
greater lengths. 

One of the most important problems for present consideration is that of 
devising the cheapest effective means of placing and holding the river in the 
new pre-determined course while making use of cheap materials near at 
hand. Along the Yellow River and at convenient intervals on many of the 
Chinese delta streams, limestone hills project through the vast deep deposits 
of silt, from which any desired quantity of stone for rip-rap can be quarried. 
In some localities, the river flows at the foot of these hills, making trans¬ 
portation by native boats economical; this fact suggests the use of rip-rap 
much as the Chinese have used it in their spur-dikes from time immemorial. 

It is quite within the range of probability that the straightening, shorten¬ 
ing, and deepening caused by the new system of a straight and narrow way 
would gradually cut down the bed of the river to an elevation materially 
below the plain, so that the great danger which comes from silt deposits raising 
the bed and from the super-elevation of the normal surface above the general 
level of the country outside the outer dike would gradually become lessened. 
As to the possibility of trouble from interference with Nature’s process of 
spreading silt from the Shansi hills over the delta surface, through arresting 
the occasional change of the river’s course, or through the more rapid exten- 


Papers.] 


FLOOD PROBLEMS IN CHINA 


1155 


sion of coast line or the shoaling of the Yellow Sea, these possibilities are 
about as remote in the future as the Cro-Magnon civilization is remote in the 
past, and present generations need not worry. 

Brushwood Retards .—There are many places where the cheapest and 
quickest means of diverting or of holding the Yellow River to a new channel 
would be by checking the current and causing sand-bars to form by means 
of a floating raft of bushy trees, if trees could be had. This part of China is 
practically treeless, and each bit of wood is so treasured by the Chinese peasant 
that it might require an army of soldiers to protect a quick-growing forest of 
cottonwoods or the like. Nevertheless, taking a long view of China’s great 
problems of flood protection and river regulation, the Government might well 
consider immediately setting apart and planting suitable trees for this purpose. 
Trees of serviceable size for these purposes could be grown long before China 
will have its river-protection works one-tenth finished. 

Training the Yang-tze 

This river greatly needs training for preventing the destruction of valu¬ 
able fertile shores by erosion and caving; also, for purposes of navigation in 
increase of depth, and a more permanent channel. For the Yang-tze River, 
with its far greater volume and depth, naturally there would be devised a 
different arrangement from that found to be most economical on the Yellow 
River. Along the Yellow River, thus far, no evidence has been found of deep 
holes being dug by the swirl of the current, to a depth of more than 30 or 40 ft. 
below the low-water surface, although possibly this may occur; but along the 
Yang-tze River in its 600-mile course from the great City of Hankow (“the 
St. Louis of China”) to the sea, the navigation charts show many submerged 
gullies more than 100 ft. and some even 125 ft. in depth. Even when a current 
of this great depth attacks a protected shore line, defense would seem to be 
possible by some such special means as trees with bushy tops, sunk by heavy 
stones tied to their stems and laid-over one another like shingles. The quick 
subsidence of the Chinese river silt favors the rapid building up of great 
deposits in eddies or where the current is checked by such material as bushy 
tree tops. 

In general, the channel will seek the line of least resistance, and in this 
delta region there appears to be an almost unlimited depth of easily eroded 
silt which can be cut at the bottom in mid-channel to any needed depth on any 
desired location; and it is of great importance that in the beginning the new 
straightened and improved channel be laid out on the best possible lines. 

Apparatus and Methods .—The cheapness with which this soft earth can be 
excavated, moved, and put in place by native labor, also must be considered 
in planning great works for flood relief. Methods that would be followed 
in America with its high-priced labor and convenient great machine shops 
would be out of place in China where earth can be excavated on a large scale 
and moved by men with native shovels and baskets at a cost of less than 10 
cents per cu. yd., and where a working force of 10 000 willing and industrious 


1156 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers. 


laborers could be quickly assembled along any given stretch of river, most 
of whom would be greatly benefited by the distribution of money. A drag¬ 
line scraper with a long boom would be useful here and there for work below 
the water level, but, in general, funds expended for manual labor would do 
far more good to humanity, distributed among the farmers for miles around, 
than if put into expensive dredges, steam shovels, and construction-railway 
material manufactured in foreign lands. 

Agricultural Improvements 

Although “Flood Problems” is the title of this paper, and the chief object 
of this work proposed along the Yellow River would be the safe-guarding of 
the many millions of population on farms and in small cities within a few 
hundred miles north and south of its course, from any such outbreak of flood 
as that of 1887 or of 1851, there would be an important incidental benefit from 
converting the strip of land, from 4 to 8 miles in width, between the inner 
dikes from its present condition of partial and hazardous use to one of 
security, fertility, and maximum use, making it comparable with the Upper 
Valley of the Nile above Cairo. On this narrow strip, vast quantities of food 
could be grown with certainty, in years of greatest drought, in the midst of 
a land where fearful famines sometimes occur from the shortage of rain. 
Some of the worst famine districts, in which the American Red Cross and 
other humane agencies expended more than $1 000 000 in 1921, are close at 
hand to the strip of “river bottom” that could thus be made sure to yield 
two bountiful harvests each year, regardless of the general shortage of rainfall. 

Regarding the agricultural development of the strip between the dikes, 
this would be subdivided into alternating tracts, the progressive development 
of which would be changed from time to time. For example, at first, there 
might be certain large areas outside the inner dike, set apart by low dikes, 
to be irrigated by gravity flow through carefully constructed conduits. The 
present super-elevation of the surface of the river above the level of this 
surrounding country could thus be made a blessing instead of a danger, since 
this super-elevation would provide the fall for distributing the irrigation 
water. To just what extent the abstraction of water for this purpose would 
be permissible remains for future consideration. 

Another means of shaping the flood-relief work for aiding agriculture would 
be by establishing impounding reservoirs within cross-dikes between the old 
inner dike and the proposed new dike, each of which reservoirs might present 
several square miles of surface 10 or 15 ft. in depth of water until shoaled 
by silting. 

These impounding reservoirs might be located on alternate sections and 
the reservoir section used for irrigating the section from which water was 
excluded by the new dike and after, perhaps, 10, 20, or 40 years, when this 
reservoir had become shoaled by silt, it could then be treated as agricultural 
and irrigated from the river by pumps of many kinds, some perhaps driven 
by wind-mills. 


Papers.] 


FLOOD PROBLEMS IN CHINA 


1157 


The Huai River Flood Problems 

The flood region of the Huai River is shown in Fig. 3 and Fig. 21. The 
American Red Cross and others are said to have expended about $400 000* in 
1911 in food, supplies, and other means of relief in the famine which resulted 
from floods along the Lower Huai River, and followed this by a practical effort to 
help prevent such-disasters in the future by sending an engineering commis¬ 
sion composed of members of the Society to China to advise with the Chinese 
on means of improvement in this Huai River District. 

Probably no place in the world more urgently needs improvement by works 
on a large scale. As has been stated previously, Mr. Chang Chien, scholar, 
statesman, and foremost Chinese industrial leader, moved by a desire to be of 
service to his native Province, had developed a school of conservancy engineers 
who had been collecting data and making surveys for several years prior to 
the coming of the engineering commission sent by the American Red Cross. 
The Red Cross engineers made a careful study of the data already collected 
by the Chinese, and under difficult conditions, made a somewhat hurried 
personal reconnaissance of the region. In the course of a few months, the 
Board submitted its report with recommendations for a plan of drainage 
channels and reclamation works, estimated to cost about $30 000 000; but no 
financing followed. 

The problem appears to have been too large and too difficult for satisfactory 
solution with the data, the time, and the means then at the command of the 
Board; and its plan of works has not been approved by the Chinese, who have 
continued their surveys more or less actively under Chinese leadership. A 
year and a half ago, Flis Excellency, Chang Chien, presented a tentative report 
for a scheme of relief radically different from that proposed by the Red Cross 
Board, calling for an expenditure, first and last, of about $45 000 000, at the 
present rate of exchange, suggesting that the work be done largely by the 
soldiers of the needlessly large Chinese Army which had been called into 
existence during the World War, and could not well be disbanded and turned 
loose without employment or means of support. Within the past year (1921), 
additional surveys have been going on and a young American engineer, E. W. 
Lane, Assoc. M. Am. Soc. C. E., recently of the Miami Conservancy and of 
the Morgan Engineering Companies, has been called to China to assist Mr. 
Chang Chien’s organization on canal improvement and other hydraulic 
problems in Kiang-su Province. 

When studied in a broad and thorough way, this problem of the Huai 
River flood relief is extremely complicated, combining river training, flood- 
detention reservoirs, irrigation supply, the exclusion of sea water from flow¬ 
ing back in the channels in time of drought, the improvement and modernizing 
of about 100 miles of the Grand Canal, as well as the reclamation for agri¬ 
culture of vast areas of shallow lake beds. As previously stated, the finding 
of a practical solution intimately affects the lives and prosperity of 2 000 000 
inhabitants in one of the most fertile regions of the world, which might be 
far more densely populated if only the present terrible succession of floods 
could be prevented. 

* See Reirisch, “An American Diplomat in China”, pp. 70-80. 




1158 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers. 


Until about 728 years ago, affairs appear to have gone on comfortably in 
this district, as affairs go in China. Then, the Yellow River broke away 
from its older channel and usurped the bed of the Huai River and by raising 
its bed with deposits of silt, and thus finally completely excluding the Huai 
River from its ancient bed, forced the enormous Huai flood volume, sometimes 
more than 250 000 sec-ft., to find new outlets to the sea, partly through scant 
sluice-ways in existing dikes and partly by way of the Grand Canal to the 
Yang-tze. 

The Huai drainage basin comprises 52 000 sq. miles, on which sometimes 
10 or 12 in. of rain falls in a single storm. The crude maps available indicate 
that more than three-quarters of the catchment area is hilly or mountainous, 
and that less than one-quarter is flat, low-lying delta bordering on the sea. 

A few centuries prior to the forcing of the Huai River from its ancient 
bed to find new outlets, there had been built across the delta, a few miles 
back from the sea, the great Maritime Dike, 100 miles or more in length, 



Fig. 21. —Chinese Map of Canals in Huai Flooded District. 


for protection against tidal waves and pirates, and the outlets for local streams 
provided through this great dike were inadequate for the discharge of the 
Huai floods of 250 000 sec-ft., or more. Thus, whenever a heavy flood came 
down the Huai River, more or less of 10 000 sq. miles of delta farms became 
submerged, while the water slowly drained off through the small seaward 
channels and down the ancient channel of the Grand Canal into the Yang-tze 










Papers.] 


FLOOD PROBLEMS IN CHINA 


1159 


River. A large part of the water did not drain off, but became impounded in 
vast shallow lakes aggregating in area about 1 575 sq. miles. 

In addition to the great Maritime Dike and the Grand Canal dikes on the 
east, and the dikes of the new Yellow River channel on the north, the great 
Ming Dike had been built south of the Huai channel about 300 years ago, 
for the purpose of turning the Huai floods toward their ancient outlet. Two 
old Chinese maps of the regiop are reproduced in Figs. 3 and 21, respectively, 
the first showing the district flooded and the second some of the 3 200 miles 
of canals and watercourses, which are at various levels and serve the three 
purposes of transportation, drainage, and irrigation, but which fail to pro¬ 
vide sufficient sluiceways and main outlets to give escape of floods to the 
sea. 

An excellent history of the Grand Canal in Kiang-su Province, witli a 
most interesting story of the successive disasters, was published by a French 
priest, Father Gandar, at Sicawei, near Shanghai, in 1903. This history was 
.derived from ancient Chinese sources and begins with a terrible deluge 2 857 
years before the Christian era. Father Gandar quotes statements from Con¬ 
fucius about the earliest section of the Grand Canal, which was built in this 
district 486 B. C. For the past 500 years, he tells a story of prolonged suf¬ 
fering from floods, and of Chinese courage, industry, and perseverance in 
fighting back these floods, which has no parallel in history. Coming down to 
recent times, he states that within the 50 years of the Kun Yan Period, from 
1746 to 1796, there were 16 years of flood, and in the 37 years, from 1844 to 
1881, he tabulates the height of thirteen bad floods. After the Yellow River 
again migrated northward, in 1851, the floods became more rare, but the 
river, during its 530 years’ usurpation of the old Huai Channel, had raised 
its bed and also had been confined by high dikes, so that, although this ancient 
channel was now empty, the Huai River could not now climb back into it or 
use it. 

The speaker was invited to study the flood problems of this region, but 
was unable to prolong his stay in China for that purpose, and purely as 
a good-will offering to the friendly Chinese, he has since spent much time 
studying the data collected by their engineers, and some months ago ventured 
to submit for consideration an entirely new plan of relief, which should take 
advantage of the discoveries about the erosion of delta silt by the Yellow 
River, previously described, and which also should give to the Huai floods the 
shortest and straightest course possible to the sea. 

The speaker also suggested that if test pits and borings should prove that 
the soil in this part of the delta was as easily eroded as that along the present 
course of the Yellow River, the erosive power of the flood itself might be 
trained to do a large part of the work of excavation and thus reduce the cost of 
the great flood channel needed to a sum within the possibilities of financing* 

Under present conditions of finance in the world in general and in China 
in particular, it seemed hopeless to raise the $90 000 000 Mex. required to 
carry out the project of relief developed by the Chinese engineers. Moreover, 

* A special paper on these Kiang-su flood problems is in preparation by the speaker, 
and has already been submitted in a first draft, subject to revision, to several of his American 
and Chinese engineering friends for their counsel and constructive criticism. 




1160 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers 





Fig. 22. 












Papers.] 


FLOOD PROBLEMS IN CHINA 


1161 


the speaker was led to believe, through a study of all the data that he had 
been able to obtain, that by means of a different plan a vastly greater area 
of shallow lake beds could be reclaimed for agriculture than had been pro¬ 
posed in either the Red Cross report or the later Chang Chien report of 
1919. 

Tentative estimates on rather bold and broad lines, from limited data, in¬ 
dicated that the value of the land that could be reclaimed would become 
sufficient to reimburse the entire cost of the necessary drainage channel and 
all the other flood-protection works required in this large district. 

The method worked out by the speaker is shown in Figs. 22 and 23, 
which present, respectively, a map of the district showing the location of the 
proposed new channel and a cross-section illustrating a possible method of 
constructing the new flood channel. This new straight channel would serve 
both navigation and irrigation and would also carry the discharge of the Huai 
River under normal conditions. 



Fig. 23. 


It was suggested that if borings and test pits showed favorable ground, 
all that need be excavated was one, or preferably two, deep, narrow channels 
inside the edges of the future main channel, which preliminary channels, 
providing barely sufficient earth with which to build the new dikes, should be 
cut so deep (about 30 ft.), that under the existing slope and brief yearly condi¬ 
tions a scouring velocity of from 5 to 8 ft. per sec. would be produced, which 
velocity it was believed would rapidly cut away and carry off, as long as the 
flood flow lasted, the silty material between these two preliminary ditches. 
The floods of several years were expected to complete the work gradually, 
aided here and there, and from time to time, by special training dikes and 
groynes and by men and baskets or by dragline excavation where necessary. 
The hydraulic estimates were worked out with considerable detail. The 
determination of the shape and depth of the preliminary channels for the 
production of maximum scour is a somewhat intricate problem of itself, 
but this paper is not the place for the presentation of those special problems, 
and this whole Kiang-su problem requires more study both in the field and in 
the laboratory. 

Such a project would not be definitely recommended by the speaker, or 
its precise location laid down, until after much preliminary investigation, 
but the hope of accomplishing the much-needed relief to the district and of 
recovering 1 000 sq. miles of the most fertile land in the world for agricul¬ 
ture, which now lies submerged under shallow lakes, in a region where 
















1162 


PROCEEDINGS, AM. SOC. C. E., MAY, 1922 


[Papers. 



Fig. 24. 



























Papers.] 


FLOOD PROBLEMS IN CHINA 


1163 


every acre is badly needed, which reclaimed land might ultimately repay 
the entire cost, seems worthy of extended consideration in comparison with 
the plan proposed tentatively by the Chinese engineers calling for an expen¬ 
diture of $90 000 000 Mex. The speaker has no other interest in this project 


PROBABLE ISOHYETALS 

OF 

MEAN TOTAL ANNUAL RAINFALL 
IN 

CHINA 


7 125° 


500 mm. 
W12 yrs.) 
Harbin 

-45H 


Based mainly upon observations made by the Jesuit 
missionaries and recorded by the Sicawei Observatory and 
upon the observation of the British Municipal Council of 
Tientsin, of the Maritime Customs at Shanghai and various 
^coastwise station^ and of the-GhilhJfiver Commission. 




580 rom.Mukdep^6 x 
* (B'yrsJ) ✓ 


/ i°' . X 

518 -Tientsiu -2 


mm. Shanhou-lO 

19 mm. Newcfiwang'fo 
yrs.)' 878 mm. Antung-15 
l (Q ( 2 .y,r.a.)-4Q2 


q... 510 mm; 

stunchiacbuang ( 

(9 yrs.iy 


Tangrku 

i yrs ) 

GULF 


0 mm. ChinwangJtacM,Z^ \ 

\ \ ^ \ 

angku-22/\ \ \ / \ 


328 mrn Tam^ 

„ (8 yrs.) 

0 mm. Weihwei. 


Position of'raingage shown thus:0 
Total precipatation given in millimeters 
The small figures at right of names is the 
number-given this station in the Sicawei index. 

Short temTobservation are_compensated| 
to a.llow for the greater or less anrhoarrainfall 
observed during tljis period by reference to I 
the nearest long term stations. 

There being no reliable records known for 
the elevated Shantung mountain districts.these 
isohyetals are drawn in by judgment after 
studying mountain contour, and noting the | 
increase due altitude from Kiu Kiang to Kujing. 

With exception Of Kuling. all stations showp are 
at an altitude not far above sea level. 

These altitudes.'are given in accompanying; 
tables. _ / 

yrs.yl 1 5Tmm.^? 1^3mm. Tungcheng-5 

" £hasi-5ou\rr77 (3 yr . s -)'~ D ~ ' 


.S^S^mrn'C 


U \ ' A 

OF PECHILI ( Chemupo 31 

°481 mm. Howki-27 (_392 mm. 

(10 yrs.) J-~x(Uyrs.) 

e f oo-3 o^600~N. E. Promontory -32 
) (49 yrs.) / 

23 mm S E. Promontory-J3 

r40 mmrtala^^<! . 

^-(4'yrs.j * .if 693 mm.Tsingtao-35 

Oirnrn.Chimrig^ (17 yrs.; 

Y E L 


»-r 


anchuanb 
'(.4 yrs. 

ll t 76 h 4t? 

"^800x X (ltef 

Jl029jnm. Nanking-4^ 

1085 mm-_1000—/ \ (14 yrs.) 

lchaag-9g —_ (l — I —-—1100 


Y E L L O 


W 



618 mm.Yentou-40 (4 yrs.) 

Suining-42 (4 yrs.) ) 

v.yN 8V (\5 Vf 8 -' 

< = ,V Sb^, e ’ shan ' 4T 
A Vkk **“(**$& Saddle is. 

^"*1120 mm. Guuiaff-55 >_ 
X\ (11 yra.) . „ ,< ~tr 
mm\ Sicawei-5l(46 v : 

. mni.Ningpo-.63 b0 

' I (11 yrs.) 



F’ig. 25. 


than that of being helpful and the attraction of a fascinating engineering 
problem. 

The straight course is proposed to be designed with dikes protected in some 
localities by groynes, somewhat as shown in Fig. 20, or on other locations, 











































1164 PROCEEDINGS, AM. SOC. C. E., MAY, 1922 [Papers. 

as A-G , A- 1, M-N, or wherever natural conditions most favored construction. 
In some localities, instead of the stone-faced spur-dike shown in Fig. 20, it 
might be better to use groynes of submerged concrete sheet-piling, reinforced 
with large split bamboo, instead of with steel rods. It would be pleasing to 
the builder to obtain his reinforcement from quick-growing plantations along¬ 
side the work. 


The Chihli Flood Problems 

A map of this catchment area is given in Fig. 24. The terrible results 
of these floods of July, August, and September, 1917, have already been 
briefly described. Most of the delta of 12 000 sq. miles was inundated, bring¬ 
ing great suffering to more than 5 000 000 people and a property loss of more 
than $50 000 000. In general, this was said to be the worst flood in 140 years. 

The conditions of soil, slope, and drainage, in this delta are substantially 
the same as for the deltas of the main Yellow River and that of the Huai, 
for all are of common origin—loess brought from the hills by floods and de¬ 
posited in vast, nearly level deltas—and all have the present rivers diked in; 
but the flood in Chihli is of local origin, from a water-shed not distant more 
than about 250 miles from the convergence of the five rivers shown in Fig. 24. 
Therefore, the Hun River floods are quicker, briefer, and relatively more 
violent, considering the small water-shed, than those of the Yellow River. 
This Chihli water-shed, as shown by the isohyetal map, Fig. 25, lies where the 
annual depth of rainfall averages only about one-half that of the Huai, but, 
nevertheless, it can have precipitation in a single storm as much as that of the 
great Miami Valley flood. 

From the manuscript of a preliminary report by Mr. H. Van der Veen, 
Consulting Hydraulic Engineer to the Chinese Ministry of the Interior, the 
following interesting facts are transcribed. The rainfall at Shir-kia-chuang, 
on the railroad at the western edge of the delta plain, near the foot of the 
hills, as recorded by the Administration of the Tcheng Tai Railway, showed 
about 40 in. of rainfall in the three months of July, August, and September. 
This three months’ rainfall is about double the average total for the whole 
year in that region. Of this, about 18 in. fell in July, and on the 26th of 
that month, 10.4 in. fell in one day, following ten days of almost continuous 
rain. This was followed by 10.7 in. more in August, and nearly 9 in. in 
September, thus saturating the ground. Although rain-gauges throughout the 
drainage basin were lacking, the fact that widespread floods were simultaneous 
on the several converging rivers shown in Fig. 24, indicates that this one 
gauging presented something more than a local condition. 

The best information now available indicates that, although a large part 
of the catchment area in the lower slopes of these Chihli hills is covered with 
loess earth, which has a remarkably great capacity for quick absorption of 
ordinary rains, the upper parts of the hills and mountains are steep and mostly 
bare of loess, having been almost completely deforested a few hundred years 
ago. 

The conformation of foot-hills and plain in this drainage area is nowhere 
favorable to building large detention reservoirs, and no detention of water 


Papers.] 


FLOOD PROBLEMS IN CHINA 


1165 


precipitated beyond the natural absorption of the soil, is practicable, except 
such as might be brought about by many years of reforesting. Immediate 
protection would seem mainly a matter of dikes and carefully planned channels 
and of building the farmhouses on mounds. 

A partial protection by detention in ordinary floods is given by the wide 
distance between the existing dikes and by the extremely crooked courses of 
the rivers as they meander between the dikes, all of which tends to delay the 
progress of the flood and to give a moderate volume of storage space when 
the bank-full stage is exceeded. Unequal delay on different streams tends 
to prevent their flood peaks from coinciding and, perhaps, it is in part this 
excess of channel length and excess of width between dikes in the upper part 
of the delta that has made the narrow, single channel within the City of 
Tientsin tolerable for so many years. The maximum discharge capacity of this 
channel at the time of the 1917 flood is estimated to have been only from 
35 000 to 50 000 sec-ft., whereas the estimated discharge in the Hun River alone 
was upward of 200 000 sec-ft. The widespread suffering caused by this flood 
was almost beyond description. 

The Chihli River Improvement Commission 

All this led to immediate action by the Chinese Government and the ap¬ 
pointment of the best hydraulic engineering talent available in China on an 
organization which developed into the Chihli River Improvement Commission. 
This Commission is still at work with a corps of Chinese engineers, under 
the advice of an English chief engineer of much experience in India, who has, 
for his principal assistants, two members of the Society. 

The message from President Feng-Quo-Chang to the inaugural meeting 
of the Commission read like a verse from an ancient poem. It was brief and 
to the point and worthy of a land great in classic literature: 

“The great flood has caused my people miseries, 

The down rush of mad water has demolished embankments and dikes, 

In haste let engineers be consulted with conservancy measures, 

For in this way the nation as well as the government will be benefited. 

The Han Emperor in person led the people to work on the damaged rivers 
And in return for his zeal, Heaven blessed his reign with prosperity. 

Let the Commissioner vie with the illustrious Emperor in the merits he 
achieved, 

And secure for modern China prosperity as great.” 

Maps, river gaugings, and many data have been secured for the rivers of 
Chihli Province, particularly for those having their outlets past the great 
commercial city of Tientsin. So far as the speaker has learned no definite 
locations or dimensions for flood-relief channels have yet been decided on, 
except a short cut across a bend through Tientsin, already completed, and 
some work in extending and deepening the defluent channel of the Ma-cheng 
Canal. 

Several tentative suggestions have been made from time to time, and some 
surveying has been done for several defluent channels, by which flood water 


1166 PROCEEDINGS, AM. SOC. C. E., MAY, 1922 [Papers. 

could be deflected from the Wei and other rivers down ancient shallow drain¬ 
age courses, across the delta to the sea, some of which may mark the site of 
prehistoric channels of the Yellow River, and are shown in Fig. 5. There 
seemed to be a popular demand for such flood-diversion channels, so strong 
that it was difficult for the Commission to resist it. 

The speaker inspected the site of the offtakes for some of these proposed 
defluents, which have been utilized to some extent in the past, but now are 
clogged with silt, and was led to believe that this method of relief by defluent 
channels as first proposed would not be permanently successful, because of 
certain fundamental principles of hydraulics, which lessen the power of a 
stream when subdivided to cut its way, or to carry its burden of silt, as effi¬ 
ciently as when consolidated in a single channel. In fact, such subdivision is 
reversing the process of Nature, which unites streams as they proceed. In¬ 
cidentally, the speaker may remark that he saw an illustration of what is 
likely to happen, down stream from any defluent from a silt-laden river, in 
the present conditions below the Ma-cheng Defluent, on the Wei River, where 
the defluent channel, or so-called “canal”, had become so filled with silt as to 
be useless for navigation during the dry season, and where the main river, 
below the point of abstraction of water, immediately becomes narrowed or 
shoaled by dropping a part of its burden of silt. The vast burden of loess 
silt brought down by the floods greatly complicates the problem. 

To a statesman or to a business man who has not carefully studied these 
matters of flood and silt transportation in the light of hydraulic science, it 
might seem that the obvious way of preventing inundations at the populous 
and important city of Tientsin would be to provide a channel for diverting 
a large part of the water before it reached Tientsin and retain meanwhile 
the present channels into and out from the city to the sea, but the great and 
uncommon burden of silt in time of flood has to be reckoned with. The speaker 
is inclined to believe that the best permanent relief would be found by con¬ 
centrating the entire flow into the straightest and narrowest channel computed 
to be able to carry the maximum flood volume. 

The best location for this channel is another question. Perhaps, this single 
river channel could be safely made narrow and diked to dig itself deep and flow 
through the midst of this city, or it could be deflected to one side and a loop 
canal built from this flood channel through the city for the needs of navigation. 

It is no small problem to determine how best to improve or to preserve 
during flood and drought the much needed, deep ship channel from Tientsin 
to the sea. It has been said that 2 000 years or more ago, Tientsin stood near 
the edge of the sea, but, because of the delta growth, it is now twenty miles 
distant from the sea, with a bad bar at the river’s outlet. The tendency of 
salt water when mixed with fresh water to cause the latter to precipitate its 
burden of silt seems to be in evidence at the mouth of nearly all these great 
Chinese rivers. 

Flood Waves 

This type of flood problem appears to be presented in the slopes of the 
Shantung Mountains leading out on to the delta plain. In the course of the 


Papers.] 


FLOOD PROBLEMS IN CHINA 


1167 


Grand Canal surveys, evidence was found of almost incredibly large flood 
volumes flowing for brief periods from relatively small catchment areas, for 
example, on the Wen River, which flows from the northwestern denuded slopes 
of the Shantung Mountains. Careful explorations were made and levels 
were run over a long series of flood marks along the river, which are un¬ 
doubtedly authentic. Their height and slope when combined with measure¬ 
ments of the cross-section of the river showed, by computations from the 
Kutter formula, a flood discharge at the tnaximum of about 330 000 cu. ft. 
per sec. from about 3 200 sq. miles, which is larger than the greatest flow 
measured at the peak of the greatest flood in the neighboring Yellow River 
from about one hundred times this Wen River drainage area, during the past 
ten years, but this Yellow River flood continues for about two months, while 
that of the Wen, the mountain torrent flood, continues great only a few hours. 

In 1914 the Red Cross engineers happened to have an opportunity to gauge 
a flood flow in the Yi River of probably 140 000 sec-ft., from an area of about 
4 750 sq. miles, and there are other evidences of extremely violent brief floods 
from the westerly slopes of the Shantung hills. 

The speaker is inclined to explain the extreme height of these floods, as 
well as their brief duration, by conditions not unlike those found in some 
parts of the Western United States which cause an extremely sudden flood, 
commonly attributed to a “cloudburst”. In these cases, an almost instantane¬ 
ous rise of perhaps 10 or 15 ft. occurs in the stream surface within as many 
minutes, often with disastrous effects to cattle or teams that happen to be 
within its reach. 

A possible explanation is that under the well-known hydraulic law by 
which the velocity of flow in a channel increases with the depth, so that four 
times the depth gives double the velocity, according to its one-half power of the 
depth, as given by different authorities, the water in the rear, having ad¬ 
vantage of the increased depth, travels faster and overtakes and piles on top of 
the earlier run-off, thus creating the great height of the advance wave. Recent 
authorities made the velocity increase in a higher ratio to the depth, some as 
the two-thirds power, some as the three-fourths power, instead of as by the 
time-honored Chezy formula. 

This particular flood phenomenon is well worthy of more observation and 
of more careful scientific study than it has yet received. 


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